The Web 2.0 Awards is a website that has “over 300 web 2.0 sites in 38 categories” – rated and ranked. There’s a winner in each category, and runner-ups are also mentioned.
It’s not always terribly accurate – for example, under the category of Bookmarking, del.icio.us isn’t mentioned (and I’d think it would be). But then, maybe the other sites listed were somehow considered “cooler?” I don’t know. Del.icio.us is mentioned in the Social Tagging category…
Still, this is a great tool to use as a summary of web 2.0 products and services, listed in categories. Go take a peek.