This article tries to explain why some websites with really ugly designs do so well regarding usage. I think it dances around the reality of the situation. These sites are ugly because they weren’t professionally designed. They were implemented to be functional and to get into the marketplace (budget/time/resource limitations). The reason they are successful is because they were either: innovative, viral (word of mouth), or just plain useful.
Design doesn’t make or break a website, the ability to expose usability and functionality of your product in a way the user can grasp with minimal effort is what ultimately is important.
The sites mentioned (Craigslist, MySpace, and Google) all have rather humble beginnings. None were started by the big companies. They were created people with an idea, not a design.
I guess it’s all about how you view things. You can either be vein, or be functional. In my opinion the gifted are the ones who are rather balanced between the two.