Triggering Google's Bot?

I've got a pretty big content-oriented site and I'm ashamed to admit that I had a lot of dup metatags. Of course, I'm going through right now and cleaning all that up and getting rid of all the dups. However, what's the latest thinking on how to get Google to look at those pages? I'm in bed pretty good with them, but, even so, will their bot pick up on the small change on a page of just modifying the meta tag description? Or are there any tricks that supposedly work to get the Google bots to scan a page you have changed?