For thos of you who use Ubuntu and are finding that the new flash player 10 is having some problems, all you need to do is remove Flash player 10 and install flash player 9 and all will be normal again. Just follow these instructions:
open synaptec, remove flashplayer, etc.
sudo wget http://downloads.macromedia.com/pub/flash_player_9.tar.gz
tar -zxvf install_flash_player_9.tar.gz
in terminal enter:
[follow the instructions]
You are now good to go. Open Firefox again and enjoy.
You can also find other versions of flash here: