Google has released a new feature in Webmaster Tools called Index Status. The feature shows you how many pages you have included in Google's index at any given time.
The feature appears in the Health menu in Webmaster Tools. It shows how many pages are currently indexed, but also shows you a graph dating back a year:
"If you see a steadily increasing number of indexed pages, congratulations! This should be enough to confirm that new content on your site is being discovered, crawled and indexed by Google," Google says in a blog post. "However, some of you may find issues that require looking a little bit deeper. That’s why we added an Advanced tab to the feature."
"The advanced section will show not only totals of indexed pages, but also the cumulative number of pages crawled, the number of pages that we know about which are not crawled because they are blocked by robots.txt, and also the number of pages that were not selected for inclusion in our results," Google adds.
When you click on the Advanced tab, you will see something like this:
Google says the data you get from the tool can be used to identify and debug numerous indexing-related issues your site may have.
Of course, the company also touts the feature as a way to bring "more transparency" to the table, much like its recent, confusing messages about links.