The best way is to read the T.O.A. carefully and you can look at many other myspace pages to see if they have advertising on them. If it is ok then more than half of the spaces will have ads on them and everyone will be trying to make money off it.
Now with that said, my experience is in contextual advertising. You will get alot of people that will tell you how disappointed they are when it comes to contextual revenue especially Adsense. You have to realize that these companies don't make money by giving you a check. They make money by figuring ways not to give you that check!
You will always see discrepencies in your earnings report, like a 50 percent drop one month and when you write to them, they tell you some line of crap that the market is slow right now! But, they are just ripping you off because they know you are a small-timer just like everyone else and can not afford to sue them over $50.00! Even the bigtime people notice the fluxuation but not as badly.
I had a blog that earned $300.00 a month and when it peaked to three hundred they changed something and now it only makes $60.00 off of the same traffic. About 2,000 hits a day. They check your refferal links to see where the people are comming from. So if it's not from a link on a laggitamate site you won't get credited. The only way to make money is to have a proffessional site that pays for advertising and the visitors come from those advertisers.
A site like this forum has many of visitors a month so it can make enough to cover the coast of operation, but by far is it making a living off of it.
My advice would be not to waiste your time unless you have the money to invest in advertising your site and have legitamate link from other sites and not link list.
Speaking of advertisements on this site......
She looks like a good match for me!
[edit on 29-10-2007 by MrMysticism]