For many mobile games publishers, Android won't really kick off until early next year, when Google allows them to charge for their games in the Android Market store.

However, some publishers (and many developers) will be offering free games when Android Market goes live later this month. And it seems they'll have a sizeable audience of downloaders when it does.

Financial site The Motley Fool is claiming that T-Mobile USA has pre-sold around 1.5 million of its G1 handsets – the first Android phone – in advance of their launch on October 22nd. What's more, it claims another two million will be available in-store on launch day.

If true, it's a very strong start for Google's new mobile OS, and will ensure a big audience on day one looking for apps to download.

The decision of big firms like Glu and Namco to release free games rather than wait to sell titles in January might have raised eyebrows, but the strategy makes more sense in the light of the strong pre-orders.

It'll be intriguing to see what free games indie developers come up with in the early days of Android Market too, though.