Steve Jobs didn’t show Snow Leopard (Mac Os 10.6!) in his keynote, it will be presented later today.
It will be an update to optimize OS X and to prepare it for the future.
More details here
These screenshots are probably fakes, but who know what could Apple announce in its anual WWDC keynote in 12 hours.


“Snow Leopard” is the code name of this upcoming version of OS X (according to many non official sources).
It seems Apple wants to get rid of the 32 bits processors to switch to a 64 bits kernel for OS X.
As a result, there will be no more supported PPC processors if this version of OS X gets released on 2009 (according to rumors).
Total support for 64 bits is also the best thing for the latest generations of Intel Processors that feels better when running 64 bits applications in a 64 bits environment.
To me, everything is possible, and I won’t be surprised if another scenario happens: a 64 bits version of Leopard to run on PC computers!
But I also do think, the fact Apple will release this OS for 64 bits processors only is not possible since the iPhone’s processors are 32 bits…
Who knows?
Apple has already sent a Beta of the next update for Leopard.
It may seem a little “anticipated” especially with the good feedback for the previous update (the 10.5.3) but i guess that’s the normal evolution pace to have a fully-optimized OS 
the 10.5.3 update brought a new featurre to Adress Book : Synchronization with Google, which finally was only possible for those who own an iPhone or an iPod Touch (so you keep your gadget, your Mac and you Google Account synchronized).
To enable it just go to the preferences panel of Adress Book.
It’s now possible to do the same thing without owning any of the portable device, just follow this How to
This wallpaper pack is really beautiful.
It remind me of Leopard’s default wallpaper Aurora, it is available in 4 colors including puple 

This trick solved many of the problems I had with Leopard: the 10 secs delay for Mail to check my email, slow connection on MSN Messenger, Adium won’t connect to MSN at all…
Two steps to fix this(these) issue(s):
- go to Network > Advanced > DNS, and add these DNS: 4.2.2.2 & 141.1.1.1, click on “Apply” and close system preferences.

- open Terminal (Applications > Utilities > Terminal.app), and type this command: sudo dscacheutil -flushcache
Now you can start your applications and you’ll feel the change!