The latest Matt Cutts missives make for very depressing reading. He more or less dismisses all of the "problems" reported via GG's email address, and once again, refers to it as though it is a "crawling" issue:
The crawl/index team checked into several reports and each time came up with other reasons why the site wouldn’t be crawled as much (e.g. the ‘next page’ url on one site wasn’t short; it was a total hairball with like 200 chars of params), and some supplemental results folks have been through the raw emails, which is how one of the site: changes was noticed. So far, about half of the feedback to the email isn’t about pages dropped. Of the other half, one factor is that several sites have spam penalties. Of the remaining feedback, the two site: changes were the only two that we noticed. We’re going to keep digging in, but people need to bear in mind that Bigdaddy does have different crawl priorities, so a site that had more pages indexed by the earlier Googlebot won’t necessarily have as many pages indexed in the future. But don’t get me wrong; we’re still going through the feedback to see if there’s anything else to be identified and improved.