I agree with Vanessa that making friends is easier online. The beauty of online, unlike real-life is, you're not stuck with anyone afterall. When you're at school, you need to be around those people whether you like it or not. Internet? You don't. It's easier to join a new website than change town and school afterall, and we have friend lists, IM's, blocking, etc. So when you're talking lots with someone online, it's because you two definitely want to, not just have to because of circumstance! Which is how any relationship should be, really. It's why most people tend to meet their other halfs when out of school, when you make effort to see eachother, not just do it at school.
I also think long-distance relationships can work, depending on the person, but not online. I don't know how people really do it. Relationship is all about being close with someone, and being intimate with them, there shouldn't be anyone closer to you in the world; I personally could never really do that from behind a computer screen. "Love conquers all" is quite nice and what many people think but, I think you need to meet before anything like that at the very least. And then I'd say it becomes long-distance, rather than 'online'. I've made so many close friends online, like I met a friend from LoZ.com I've known for what, 6 years online when I was down in London and he showed me around and stuff and took me to his for lunch, was lovely, but I'd never consider any form of relationship online. That's just me. I've been in long-distance but it didn't work.