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As mentioned above - changing URL's is a bad idea more often that not, but considering that you've already done it, you'll just have to wait to see the changes reflected in Google.
When I did it, I did it when my site was down for like a week, in the middle of that week Google update itself and my site went from a PR4 to a PR1, to a 0. I also wasn't using Google SiteMap either. Once I update my site and got it back up all with the new urls, my page rank in matter of a months time went back to PR4 on the main page and about 1/2 on others. The big thing though was my ranking start to go back up and I saw the new pages show up in searchs.
So its all in when you do it and the reasons. If your pages don't see it, your better off not changing it if you have high ranking/high traffic unless you want to take the time and 301 every page to the new page which can be a bit bother some.