loosing vi mode in terminal
Solution 1:
You can use C-xC-e to go into editor mode. This will use vim if your $EDITOR is set to vim. Also, if you switch to zsh there are options to have a psuedo-normal mode on the command line. See this blog post describing it: http://www.civet.ws/?p=165
Solution 2:
If you're using set vi then C-xC-e will not open your editor as Conner suggested. Instead, use Escv.