If you are considering using Social Networking sites as part of your overall marketing strategy, you might want to check out www.usocial.net
Now they've been around for a couple of years, but I'm only in the process of learning a bit about this company myself now, so I can't recommend the products they offer. However on the face of it, and from what I have managed to learn about them so far, they offer a very interesting range of products based around bringing traffic to your Social Networking efforts.
I was made aware of them through a local TV news story a few days ago. I actually contacted and spoke with the producer of the story itself a few days after it ran, and inquired as to how deep their research went.
Typical fluff story, basically a leader from a newspaper story on the company as it turns out, however the switchboard hadn't gone into meltdown with people screaming about being taken for a ride by the company in the preceding days after the story aired, and the producer wasn't aware of any serious negative publicity out there, so it's a good start.
One of the key questions is just how targeted that traffic actually is, and I'm in the process of trying to confirm that with them.
Anyway, drop by and take a look for yourself, and drop in a post if anyone does have any experience with this company, or any information at all. That would be much appreciated.