Even for a publicly owned company, freemium social outfit Glu Mobile (NASDAQ: GLUU) is incredibly open when it comes to talking about its revenue sources.

More than breaking it out on a per platform basis, the company drills down, detailing specific games, revenue from certain carriers, as well as from different types of transactions.

"We're in the credibility business. We're educating people about social games," CEO Niccolo de Masi explains.

The result, combined with additional clarification during a question and answer session, provided a fascinating reveal of where the company, and the wider mobile industry, is heading, so here are eight things we learned from Glu Mobile's first analysts day, held on May 26.

1. Ads will win out over IAP for freemium games

As a rough breakdown, micro-transactions and in-app purchases currently make up 50 - 60 percent of Glu's smartphone revenues, advertising with standard display ads accounts for around 10 percent, and incentivised ads 20 - 30 percent.

However, over time, Glu expects this to change, with micro-transactions' percentage share dropping as the mobile ad market becomes more mature, in terms of available ad units, and as CPM rates rise to match those for web advertising.

Another reason is advertising generates revenue from everyone who plays a game, not just the 5 percent who are prepared to spend real cash in-game. As billions of people get smartphones in future years, that's going to be a lot of eyeballs.

But there's still some way to go. "Filling mobile ad inventory remains an issue at the moment," de Masi confesses.

2. New ways to incentivise

Glu made $2.2 million in its first quarter of 2011, and $2.9 million in the first two months of its second quarter, from incentivised actions (CPI), such as giving people in-game currency for downloading advertised apps and games from third parties.

However, with Apple stamping down on such practises, Glu has stopped supporting it, removing such code completely from its games. Of course, incentivised downloads are still available on Android, but Glu says it makes less than $200,000 per quarter from CPI on that platform.

Instead, on iOS, it's switching to other incentivised actions, including giving virtual currency to players for inviting their friends to download its games (what’s labeled CPA), or for watching a short video (CPE).

De Masi says he expects Glu to replace 50-75 percent of CPI revenue with these new actions in the coming months, with CPA and CPE revenues becoming larger than what CPI would have generated in the longterm as they become more popular with advertisers.

Indeed, he's so bullish on incentivised actions, partly because of the way it leverages Glu's in-game currencies, he expects it will eventually become a larger part of Glu's revenues than IAP.

3. Gun Bros. is a $10 million a year franchise

De Masi has long argued the smartphone games industry has to be able to create $100 million franchises in a way that happened on feature phones (I-play's Fast and Furious games for example.)

Glu isn't there yet, but its signature title Gun Bros. generated $2.3 million in Q1 2011, so it's on track to become a $10 million a year franchise, especially as it's about to get a substantial social and multiplayer update.

This makes it a highly profitable title too, as it cost around $500,000 to develop (taking 65 man-months), and has cost a further $500,000 to support and market in the five months since.

4. Android, where art thou?

Despite the fast increasingly parity in terms of number of iOS and Android devices, Glu's revenue from Android is only around 10 percent of the revenue generated by iOS.

Partly this is because Glu has more titles that have been live longer on iOS, but even on an 'apples to apples' comparison, an Android gamer is currently only as third as valuable to Glu as an iOS player.

This is important as Glu is the most voluminous games publisher on Android, and was a launch partner for Amazon's Appstore for Android. Still, de Masi describes Android a "massive opportunity", both in terms of how quickly it's growing, as well as the expectation that the value of its gamers will eventually move closer to parity with iOS.

Indeed, there's an line of argument (radical perhaps) that if new forms of incentivised actions work out as hoped, Android gamers could be worth more than iOS gamers, especially if Apple keeps restricting its in-app purchase policies.

5. The time is now

Are we experiencing a social games bubble? Certainly, many people in the industry think Zynga's expected IPO is exciting investors into a fit of irrational exuberance.

Still, Glu hopes if Zynga floats successfully, it will improve its own valuation as investors understand more about how the social games market works.

But what's more important to Glu is the speed of addressing a different land grab - the fast growing smartphone market - as well as riding the wave of consumer interest in particular game themes.

Answering an analyst's question about the cost of game development, Glu's CFO Eric R Ludwig said, "We worry more about the time of development than its cost."

He added, "Opportunity cost is more important than actual cost. Cost inflation might be two-fold, but the potential upside of getting a hit game is 10-fold."

6. The pace is brutal, but quality counts

Committed to release 20 to 25 games in 2011, Glu says it's improving its hit-rate, as well as gaining experience in terms of how long to support games that don't immediately find an audience. Most games will at least get one update - an opportunity to refresh and repromote them - but none will get more than two shots at success.

"Some titles we cut the week after launch," stated Eric Ludwig. "Magic Life was a dog from the get go."

"Our failures have tended to be cheaper, less innovative titles, and ones that aren't in the action-adventure genre," said de Masi.

7. We haven't been social enough

Perhaps surprising for a company that labels itself 'social', nevertheless de Masi said, in comparison to Facebook publishers such as Zynga, Glu hadn't been social enough.

Partly that's due to the relative failure of services such as Apple's Game Center, OpenFeint or Plus+ to provide a social mobile platform that's focused enough for big publishers such as Glu to use. Hence, in the summer, it will be rolling out its own system - the Glu Games Network.

Described as a one-stop social shop, this cross-platform HTML5-based network will integrate with Facebook, Game Center, Twitter, MySpace and OpenFeint, enabling players to connect with their friends, both in a general manner as well as with game-specific options.

For example, the real-time multiplayer update of Gun Bros. will also include incentivised challenges and 'Bro Buff' gifting, while new game Space City will enable you to visit your friends' cities to build special buildings.

It's an approach publishers such as Gameloft have always employed (it has Gameloft LIVE), while other outfits, such as Korean publisher Com2uS (Com2uS hub), are now taking a proprietary approach too.

8. It all boils down to eyeballs

The power of the freemium business is that you give stuff away for free. This makes you very popular, especially, if like Glu, the stuff you give away is high quality. Last quarter, it gave away 20 million games, and 12 million people play its games every month.

In one respect then, how Glu monetises its players is irrelevant. In a good ecosystem, there will always be plenty of companies providing interesting services that transform attention into cash. All Glu needs is those eyeballs.

However, as a public company, it's very relevant for Glu's shareholders how well it monetises its players, which is why Apple's recent change of attitude over CPI was a big deal, and why Glu has been public in talking about the situation. Such unpredictable shocks are bad for business.

Still, the hope is as the industry matures, especially on Android - where Google has demonstrated almost no interest in regulation beyond what's legally required - the growth in eyeballs will be so fast, and the available services so attractive, the value each freemium gamer’s attention is only going one way - up, up, up.