hey yall,
was having the same issue with this.
turns out (for me anyway) the issue is user role related and not browser related.
the upload/image toolbar disappeared for me completely when i assigned a user to be a contributor, but reappeared under other higher level roles.
FF (5.0), safari (3.2.1), OSX 10.5.6, FlashPlayer 10, WP 2.7.0
