I find it surprising Craigslist is missing from this list.<p>If you take a closer look, all of given examples have really polished up their design over time as they became more and more successful (well... except myspace that is).
I used to work in a lumberyard with several insanely insensitive men. They had a saying which applies here that I will not repeat.<p>I think that the super slick look can actually hurt an app.<p>www.gowalla.com comes to mind.<p>Enormous cuddly looking stuff makes it hard for me to know where I'm supposed to focus.