Over the last few months there's been a feeling that we need a centralized database of Web 2.0 apps. I've always intended to try this out with my Weblist blog, but other projects have a habit of getting in the way. Luckily, lots of enterprising folks have stepped in to build the grand-daddy of Web 2.0 company directories. Ironically, there are now so many of these sites that it's proving hard to keep track of them all. There are also a few Web 2.0 blogs that let you navigate the company listings via tags - I've left those out of the list. And since this is one of those posts that's never really complete, feel free to add more Web 2.0 directories in the comments.
BuzzShout - Excellent directory of Web 2.0 companies. Impressive. Includes site submission, ratings, tags, user profiles, and logo surfing. However, its openness might be problematic: many of the Web 2.0 companies listed seem to have been submitted and rated by the company creators themselves.
Web 2.0 List - simple memedigger for Web 2.0 companies. Vote on companies, add comments and explore using the tag cloud. Also links to Alexa, Digg, del.icio.us and Techcrunch tags where available.
Web 2.0 Logo - From the makers of Web 2.0 list. The difference is that you can explore companies based on their logos. And let's face it - the logo is the most important part!
NEO Binaries - Wow. Really slick and thorough implementation of a Web 2.0 directory. Calls itself "download.com for Web 2.0 companies". Includes screenshots, reviews, categorization, ratings and more. You can also subscribe to the latest applications via RSS. Really, really nice. Probably my favorite of the bunch, although it does list less companies than the other directories.