Just a quick mention, but the Startup-Review blog has some great reviews of successful internet companies. Myspace is the latest review, but the site has also analyzed Flickr, Rent.com, Craigslist, and Advertising.com. Thanks to Guy Kawasaki for bringing the blog to my attention. The next company I would love to see analyzed- Salesforce.com. Perhaps Zillow (my employer) will be covered at some point down the road.