I met my fiance online - we happened to be living only about 20 miles apart but we exchanged emails for about 6 months before we actually met. Having said that we emailed as friends, it didn't become a relationship as such until our 3rd meeting! But it was a good way to start getting to know each other.
Now we have been together almost 3 years, I have moved to Japan to be with him (he is Japanese, he was studying in the UK) and marriage - even trying for a baby - is definitely on the cards in the coming year.

I'd say online relationships are a good way to start, but it has to become a RL relationship at some point if it's going to work.