I had been using Facebook for a while... It has a minimum bid of 10 cents. I was able to get a dozen or so hits a day with 15 cents as my maximum bid.
Myspace started getting me a couple dozen clicks a day, while my Facebook clicks skyrocketed and hit my $25 daily limit for a week straight. Financing this out of my pocket money, I cannot afford $25 dollars a day so I had to lower my bid back down.
...This leaving me with the conclussion that MySpace advertising is a waste of money. At least looking at the cost per click. MySpace does show your ad in a big banner though. This works for increasing brand awareness for a company such as Coke, or for a new movie. But for a startup like NoFouls.com, there is no value in showing an ad if the user is not going to visit your site.
So MySpace is a terrible place for startup advertising, Facebook eh... not so bad.