Collecta purports to pull in blog posts, comments, Twitter and Identi.ca updates and photos concerning your search query, as fast as technically possible. There are some rough edges for sure at launch, but Collecta has a lot of promise. Pagerank or other systems of authority are in many cases not what you're looking for in search - timeliness is.
Three of us at ReadWriteWeb tested Collecta this morning and only one of us got a consistent flow of new results coming in. It was slow and choppy for two of us, on three different internet connections. The ability to filter out certain kinds of results, to run multiple persistent queries at once and to preview items before clicking off site to read them were all great features.
Twitter search results, unfortunately, link out to a user's front profile page, not the particular Tweet that is shown on the results page. We imagine that's a small oversight that will be fixed promptly.
Blog posts are limited to WordPress.com blogs at launch, as the companies have common investors and an agreement. Sometimes filtering for comments on blogs brings up results when filtering for blog posts does not.
Despite warts and bumps, there's really nothing else quite like Collecta available on the market right now. It's a good way to get a handle on the real-time flow of information about a topic and it has an incredibly strong team.
We expect real time search to be an important part of the search world as Twitter search has already changed the way we research things online dramatically. Expanding that out into more media types is something that just has to happen.
We'll be keeping a close eye on Collecta as it expands and improves.