I recently added the www to my domain name and am waiting for Google to re-index my pages with the www in the url. Its been about two weeks. Does anyone know roughly how long G takes to re-index pages?
Depends how popular your site is. Popular sites get re-indexed faster than others, so it's hard to tell.
You can set the frequency of how you want Googlebot visit your site in the Google Webmasters Tools. Set it to the maximum.
go on Google Webmasters as the poster said above, adjust the crawl rate to maximum on the URL/website you wish to change, then google will increase the frequency the robot will come to your website, this increasing the number of pages that will be indexed.
Some within 48 hours. Sometimes 2 weeks. Sometimes they will never refresh again. (Cause I experience once.)
it depends on how Google often visit your site... try to build links on place your Google regularly visit and also pinging the page would also help.
visit google support forum to find out your answer: http://www.google.com/support/forum/p/Webmasters/thread?tid=2f2a75c5d87625e5&hl=en