Apple to show off iOS 5, iCloud, Mac OS X Lion at WWDC June 6

Apple announced this morning that it will be kicking off the festivities of its Worldwide Developers Conference next week with a keynote led by CEO Steve Jobs (and other executives) covering iOS 5, Mac OS X Lion, and its long-rumored cloud service iCloud.

The announcement cements the fact that this year’s WWDC is all about software. We already knew that Apple would be dishing out more details on OS X Lion at the event (we already caught a glimpse of it in February), and iOS 5 seemed like a given as well.

But the announcement is definitely a strange way for Apple to reference iCloud, a service that has been talked about for some time but never acknowledged by Apple.

So what is iCloud? Apple’s doesn’t offer up many details, but at this point we can assume it’s the name of Apple’s online music service. And it could also serve as an upgraded version of MobileMe, Apple’s subscription-based file storage, mail and calendar syncing service. I suspect iCloud will make it easy for consumers to store their media files online and easily retrieve them via the iPhone and iPad.

Apple has been building up a data center in North Carolina for some time, and it’s also piecing together a smaller data center in Santa Clara, Calif., both of which are expected to serve at the heart of Apple’s cloud services.

The company will definitely have some surprises in store for its WWDC keynote, but at this point it doesn’t seem very likely that we’ll see new iPhone hardware at the event.