The press release for the GNOME 3.0 release can be read at GNOME.org that details some of the improvements. The GNOME Shell, Mutter, Zeitgeist, GTK+ 3.0, etc.
For those not interested in trying out GNOME 3.0 without compiling the horde of packages, one of the first and best distributions to experience the GNOME 3.0 experience is with Fedora 15. By now though most are familiar with the GNOME 3.0 experience.
Meanwhile, the 5th Linux Foundation Collabotation Summit is getting underway at the moment (not the best day for also having the GNOME 3.0 release). I'm not here for providing coverage of it on Phoronix, but rather Matthew Tippett and I will be speaking about OpenBenchmarking.org / Phoromatic / Phoronix Test Suite improvements tomorrow during the LLVM track. However, if anything interesting is said from this San Francisco summit, there will be word of it on Phoronix. I'll also be tweeting any interesting notes via @MichaelLarabel on Twitter.