Boom Town claims several sources have confirmed that Apple is getting into the in-app advertising business by buying AdMob competitor Quattro Wireless for $275 million.

Since Apple currently dominates the mobile app space, bolstering their cut of profits with a cut of in-app advertising is likely good business for them. It's all about the eyeballs, and if those eyeballs are locked on iPhones and iPod touches, why let Google gobble it all up?

If rumors are true that Google bought AdMob out from under Apple (much like Apple bought online music streamer Lala out from under Google), then switching targets to an AdMob competitor couldn't have been entirely off the radar, now could it? (Especially with -- yes more rumors -- of Google now turning towards Spotify for their music fix).

Apple and Google certainly look to be getting even more up into each others business, and that should make the expected Nexus One announcement later today, along with Apple's expected January 27 event, and the whole of 2010, a lot more exciting!