Open GL seams a little flaky, not much just a bit. It my be my aging ATI video card that originally shipped with my Mac. But overall it does seem to run snappier than C 1.1.
The Vortex modeler is working super stable, and I am able to select points that on version 1.1 took several clicks. This is a great advantage for this modeler. What doesn't seam to work good is that if you change tools, they don't change the cursor. I am not sure if this was the case on version 1.1.
The subdividing smoothing works great and what I love is that you can go back to the simpler mesh at any time.
Importing texture Maps is greatly improved. It now happens almost immediately as opposed to weighting a few seconds or maybe longer on the earlier version.
Some thing that some one brought up and I am too experiencing, is that in the Spleen modeler, if you select one of the points, it doesn't highlight by it's self, put rather highlights all the points of the segment. Aside from that it seams to work good.
Setting up bones works good and fast.
In my experience if you like Carrara 1.1 I can't find a reason not to recommend to upgrade if you have the means. The new GI rendering engine, although I think is going to take some getting used to, produces some pretty impressive output from what I have been able to read and do.
I still think that they have a ways to go in perfecting Carrara, but version 2.0 running under native OS X, with is multiprocessing support is almost required upgrade to any Carrara/Mac user.
I really don't have any serous gripes up to this point.