I just started learning vim. It would be great if someone made a game for learning that taught some simple commands—something along the lines of, "Perform the needed operation(s) in the fewest number of keystrokes possible." For instance, add an attribute to an html tag with your cursor at a certain starting point on the line. Then have a leaderboard of the shortest key-combos used, with comments.
I'll bet more experienced vimers could learn something from this, too.
Thanks! That's definitely getting there. It would be even better if I could do it in the browser, with simpler challenges to start out. Maybe a few intro tutorials or the like.
Here's my advice. Instead of trying to learn all of these tips at once, bookmark the page (or leave it open), and try to use one of the tips at a time for at least a week. If you focus on one at a time, you'll get a much better feel for when the command is actually saving you time/thought. Also, they'll stick more permanently in memory/muscle memory.
$ vimtutor is great. Do it a few times until you don't need to read it. It's not really game-y but it's quite challenging when you come from TextMate world.
Also there is a site called http://openvim.com that works more or less like what you describe. I hate it, though. I can't bear the tone and the forced jokes and it's nowhere near as well thought out as $vimtutor.
Others have pointed at vimgolf.
One of the cool things about Vim is that you always learn new tricks.
I'll bet more experienced vimers could learn something from this, too.