Two things I want everybody to check:
1. Clear your browser cache. Really. Don’t ask silly questions like “why”, just please try it. I admit that it’s thin and probably won’t work. Try it anyway.
2. Do a manual upgrade in the following manner:
a) Get a fresh copy of 3.3’s zip file.
b) Unzip it.
c) Using your FTP or upload tool of choice, upload the entire thing right over the top of your existing installation. Pay special attention to the files in the root directory. Not just /wp-admin and /wp-includes, but all the files in the root as well, such as wp-settings.php and all that.
I fully admit that these suggestions may not work. But if they do, then please report back that they did.
Additional: We’ve seen “editor not appearing properly” problems on these forums before, pretty much every other major release. In every case I’ve ever checked myself, the problem was due to an incomplete upgrade in some manner. This is why I highly recommend triple checking with suggestion #2 there, and ensuring that you have indeed upgraded *all* of the WordPress files.