Highlights of Mac OS X Leopard: By Steve Jobs Keynote at WWDC 07
Apple chief Steve Jobs revealed in gory details the Mac OS X Leopard at the WWDC 07. It looks great and will sell for an affordable $129 (For all of its version 
i.e. there are no different version of Leopard, one version for all purpose).
He threw the concept of providing solution in that way that it is used by EVERYONE.
Apple says that you get more than 300 new features with this 64-bit OS X update. The highlights are the new cool desktop with stacks, Finder with music cover browser, Time Machine backup, Quick look WebClips, DashCode, and the cool new iChat.
Apple will enable 3rd party developer support on the iPhone. They do it with Web 2.0 technologies like Ajax, to keep the core of the phone save.
The 3rd interesting announcement is Apple releasing Safari 3 web browser on Windows.