Blekko announced an update to their index where they are aiming at not necessarily massively increasing the size of their index but rather increasing the speed in how they update the index they already have. They want a fresher and almost real-time index, very much like Google has.
The way Blekko pitched it was as an SEO tool. The title of their blog post was "Blekko Upgrades SEO Data." I mean, they are a search engine that people should use to search. But I guess this means that most of their users are SEOs using their SEO tools.
In any event, Blekko does have some nice SEO tools that you can use.
Forum discussion at WebmasterWorld.