I'm not overly excited as much as thinking "It was about time!". Interface-wise, i.e. with Finder and multi-screen, it seems like it's playing catch-up to competing systems, like Ubuntu Unity, which looks like OSX with the dock, but has addressed these issues. Nice of Apple to fix it as well. The multimonitor space scrolling may boost my productivity, so thanks. I hope they still unveil some feature that makes it revolutionary, in the same way Lion was to Snow Leopard (most notably, system-wide Autosave/Versions/Resume, great safety nets that other OS can't replicate).
Regarding CPU/memory management improvement (if it works): I don't care that much; my rMBP is already a beast, I don't experience delays. I wish and hope they'll improve the rMBP rendering quality instead.
The name Mavericks is too American and not as cute as cats. It also is like the Windows codenames (not even release names): Chicago, Memphis, Longhorn
I prefer they used the Apple wine names as official names now 🙂