Linux is awesome. The combination of this new speedy computer and well-written software act like the "Super-pursuit mode" on KITT! I'm flying through my mountains of email (745 megs, 33764 messages), and recompiling programs on-the-fly with no loss of performance.
The whole window manager feels quite refined, something I wasn't really expecting. Kudos to the KDE 3.3 team. From nice smooth borders on windows, to the anti-aliasing of all text on screen. Their support for xinerama is awesome too, snaping to the sides of my monitors and launching new windows in the currently active monitor...better than windows could do!
Here is a cool screen shot of my new desktop.
Yup, thats an RSS news ticker and weather indicator on the right hand side of the screen :)