Seriously though, you need to find a "niche" that isn't already being done. There are sites out there already that pretty much cover what you are doing. Facebook for one (which your front end looks uncannily similar to), Wegame is another and there are a fair few other lesser known ones out there too.
The point is, unless you can offer something not already being offered elsewhere or can do it significantly better, you're going to find yourself on an uphill struggle and your hill is going to be a slope of almost 90 degrees.
I've already been there and done that myself, so I know how disheartening it can be. But I'm sure you'll find your niche if you look hard enough. Good luck!

Hey, that was my idea: an anti-social networking site, a place we go to be alone on the internet.

I would seriously go there. :D

I LOL'd hard
You, sir, have won the Internets.
+rep

Cynical, perhaps, but that is not the point. Above the average age on gaming sites, that is the point. Like I said, GOG may not be the best place for you to ask about this, as the people who would most likely be interested are probably younger than us.

i use facebook for local friends and family, but thats it, mainly because it isn't as horrible as myspace (don't even get me started on myspace)
but yea, no good 'old' gamer here (seeing how they are all old) is into that stuff, but i can list a few sites for you to start your advertising...

well to be honest i to don't need another social networking thing.
I use xfire and steam.
Let' take facebook for instance :
I'm not overly interested in what a strange guy is doing in his spare time , and that the cat is having 4 kittens but 1 of them has a lazy eye and is hungry and is now away to the grocerystore. Or that god knows who coloured his hair and is now bald.
Or a weird message that tells you that someone which name is longer than your screen want's to be your friend.
On the other hand , i'm feeling quite at home here at GOG since i joined a few months ago even when i decided i didn't need another forum.
So the best off luck m8. (and that's not meant sarcastic or cynical)
So there must be a market for it.
You always need guys to develop new ideas so if you come up with something special and interesting then i might even join ;)