I upgraded several WP sites to 2.1.2 and all but one were fine. On one site, I've noticed two things missing so far:
1. The Register link doesn't appear in the sidebar or on the login page (the WP register code is in place).
2. In the editor, only the Code view appears, no WYSIWYG editor.
I've tried deleting everything but config, themes and plugins, and reuploading and no relief. There's nothing I can think of that's different with this one site than three others, which were all upgraded with the same 2.1.2 files and work fine.