tedster - 7:56 pm on Nov 22, 2010 (gmt 0)
This sounds like Google has repaired some of the inaccuracies that the site: operator has been showing for a while. In other words, the index does not really include more pages but the site: operator results are not quite so buggy.
Some detail: when the site: operator took a nose dive, I did some research for a few client websites and quickly saw that the drop was just buggy information - many pages were still in the index and drawing traffic, even though site: did not show them any more.
I just spot checked a few website, and it does look like they're back to reasonably accurate levels again.