I don't see a problem with wanting a committed relationship and stating that early on, but if that's one of the first things you say to someone you just matched with, it can be a lot of pressure. Take some time to get to know someone, then organically work in that you prefer serious to casual. In this particular case, he wanted to know what I was looking for right after we had just said "hi." It was like, "unless you want the same things I want we shouldn't go past hello." I thought that was a bit too much too soon...