[super_mario]

Not really. VIM has vi as subset, and plain vanilla vi is still quite powerful text editor. It doesn't have a lot of bells and whistles, and I would not choose to use it as the primary editor for all tasks, but if I'm on a system where I have to edit something using plain vi, I won't have a hard time doing it and doing it fast.

[chalst]

You really don't find yourself trying to use vim extensions when you use vanilla vi?

[super_mario]

No, because I know I'm using plain vi :D. I spent a good deal of my life working with plain vi, and the company I work for makes a port of POSIX APIs, UNIX shells and all typical command line utilities for Windows, which includes vanilla vi. So I'm used to it.

I use VIM with only a few extensions (taglist, command-t and snipMate). I also use ctags and cscope, but support for those is built into vim. I really try not to get too dependent on extensions. They are more like convenience rather than something you don't know how to do without. Command+T for example is useful, but you still should know how to get to your files from the command line.