Erm, right, I can really see you've seen it for what it really is then....
Oh no wait, you've not.
Let's see, I'm in my mid 20's and arbitrarily useless at keeping in touch with people. I've lost contact with countless friends over the years, and it's always been an annoyance. With Facebook, i've found it incredibly easy to get back in touch with people who I've not seen nor heard from in donkeys, which is pretty damn helpful if you ask me.
Yes, I'd like to go to the pub with them, but they live many, many miles away. Hmm, with the exception maybe of a mate I hadn't seen since primary school, who I went for a night out with the other week. Yes, clearly just an outlet for emo's
Also, unlike myspace, facebook isn't a visual assault of galactic proportions, with people who know sweet FA about how to make a site look nice, chucking garish graphics left, right and centre.
With regards to the advertising.... erm, can't see it being a biggy. I'm barely tempted to click on the relevant ads I occasionally see as it is - at the end of the day, I'm there to "socialise", not buy things..
Plus, $15B!??! Pissing joke..