Googlebot activity reports
This feature gives you a good sense the load Googlebot is putting on your server. It displays a graphical representation of pages crawled per day, number of kilobytes downloaded per day, and time spent downloading a page.
Crawl rate control
If you find Googlebot is hitting your site too often or you wish it came around more, this new feature can solve your problem. There are three options to choose from: slower, normal and faster. The "faster" option is only available under some circumstances -- Vanessa Fox explains, "If we feel your server could handle the additional bandwidth, and we can crawl your site more, we'll let you know and offer the option for a faster crawl."
Enhanced image search
This lets you opt-in to tools like Google Image Labeler which produces very relevant tags for your images without needing to describe them yourself.
Number of URLs submitted
And last, you can now see the number of URLs submitted through sitemaps. This can be useful for some people as Vanessa tells us:
"Recently at SES San Jose, a webmaster asked me if we could show the number of URLs we find in a Sitemap. He said that he generates his Sitemaps automatically and he'd like confirmation that the number he thinks he generated is the same number we received. We thought this was a great idea. Simply access the Sitemaps tab to see the number of URLs we found in each Sitemap you've submitted."