It appears that the Google Toolbar's Spell Check feature is incompatible with WWF's Rich Text Editor in FireFox. It seems to work on all other websites, just not in WWF.
What happens is you click SpellCheck and try to check your spelling, it starts the check just fine. However, when you click Stop, it does not work and WWF saves the markup that Google Toolbar has used to indicate misspelled words.
This isn't as important as the other stuff, but you should be aware of it. I'd rather have you finish version 8 than work on this bug, however. After version 8 is done, then get to this bug... unless you can do it quickly... but I'd rather have version 8 stable as soon as possible.