Yeah, I agree with that (and I don't know what I was thinking when I deleted Web from the first poll. Good grief).
However, I think when this poll started Glitterdust and Web were #1 and #2. But, as we get more votes (currently 70), Invisibility is #1 (makes sense to me), Glitterdust is #2, and it looks like Web is about to slip down to #4 after Scorching Ray.
Anyway, we can probably all agree that more votes are better.