Apple is conducting its annual Worldwide Developers Conference (WWDC) from June 6 to June 10 at San Francisco, with CEO Steve Jobs and a team of Apple executives kicking off the Conference with a keynote address on June 6 at 10:00 a.m.

If reports are true, this WWDC could well be one of the landmark event for Apple and its users as the tech giant is expected to announce some major changes to Apple's desktop and mobile OS that may narrow the gap between Macs and iPod or iPhone or iPad and connect everything to the cloud.

No wonder, the event was reportedly sold out within 10 hours of the 5,000 tickets being placed on sale on March 28th, 2011 despite the ticket price remained the same from the 2010 WWDC, selling at about $1,600.

Apple confirmed that it will unveil the following new things at WWDC

Lion Arrives:

Apple will unveil its next generation software Lion, the eighth major release of Mac OS X, which is Apple's desktop and server operating system for Macintosh computers. The latest release is expected to feature many developments made in Apple's iOS, such as an easily-navigable display of installed applications, to the Mac, and will include support for the Mac App Store.

iOS 5

Apple will release iOS 5, the next version of Apple's advanced mobile operating system which powers iPad, iPhone and iPod touch. iOS 5 is said to feature a completely revamped notification system and widgets, according to TechCrunch.

iCloud On The Horizon

Apple is also expected to unveil  iCloud, Apple's upcoming cloud services offering. There were media reports that California-based Apple has struck licensing deals with major music companies for its new iCloud service. A Bloomberg Businessweek report also says the service will scan the user's entire iTunes library and allows a user to access the same songs from any Apple device. It also said the service could replace low-quality songs with better versions, automatically.