Pretty much everything in the GNOME software stack has been touched, and it shows - GNOME 3.0 looks nothing like GNOME 2.x. The main culprit is the new GNOME Shell, which works rather differently compared to not just GNOME 2.x, but to pretty much everything else out there. As Jon McCann, a GNOME Shell designers, explains: "We've taken a pretty different approach in the GNOME 3 design that focuses on the desired experience and lets the interface design follow from that."
Since I personally haven't yet had the chance to use GNOME 3, I find it very hard to really say something sensible about such a radical departure from convention. I have my reservations, surely, but then, they are based on absolutely nothing and as such, aren't worth a single thing. So, let's just continue onwards to the other aspects of GNOME 3.0.
"The GNOME 3 development platform includes improvements in the display backend, a new API, improvements in search, user messaging, system settings, and streamlined libraries," the press release notes, "GNOME 2 applications will continue to work in the GNOME 3 environment without modification, allowing developers to move to the GNOME 3 environment at their own pace."
The release notes aren't here yet, so we'll wait for those to officially arrive (in roughly two hours) before we can fill this story with some more details about GNOME 3.0.