It certainly looks like a good time to be in the mobile advertising business – companies are being snapped up like hot cakes. On Wednesday, mobile browser king Opera acquired AdMarvel for a reported $8m in cash and the promise of a further $15m if targets are met.

AdMarvel, based in California, is a startup firm running a mobile advertising ecosystem with service offerings including mobile web, WAP, SMS and in application advertising.

Opera intends to combine AdMarvel’s monetisation and analytics platform with the Opera browser and widget platform to offer advertising options to mobile operators and content partners on any Java capable handset including Symbian, BlackBerry, Palm, Windows Mobile and various flavours of Linux.

“In our fast-growing industry, mobile advertising represents an interesting long-term revenue opportunity. Every month, nearly 50 million people access the web using Opera on their mobile phones,” said Lars Boilesen, CEO of Opera.

Earlier this month Apple acquired mobile advertising firm Quattro Wireless for somewhere between $250m and $275m, perhaps paving the way for Apple to offer an advertising platform to its App Store and iPhone customers.

While late last year, Google upped its game in the mobile space with the purchase of AdMob for $750m. Google and AdMob currently specialise in different areas, with Google’s focus on mobile search ads, while AdMob’s focus is mobile display ads and in-application ads.