I've been getting my students to sign up for friendster. But it's been really uninspiring for them, because friendster is constantly broken.
The usability changes suck too. They've removed the best part of it, how it automatically shows all the connections from you to who you are looking at. Now that info is hidden a click and a long load time away. Also, now everyone on the network is viewable, but since most of them aren't closely connected enough, when you click on them nothing comes up. It was way better before when pictures of people who aren't in your network weren't linked to anything.
Also there are the regular problems, like how I can never send a message to anyone, it takes like an hour for someone to show up on the friends list, even when they show up the system claims they have no friends.
I'm disappointed, because I'd hoped to set off a chinese english student friendster signup mania. Or at least get it banned by the great firewall of china...