Eh... I'm one of those people who think "I love you" comes out too strong. I made the mistake of using that on the first girl I ever confessed to and she was like: "I like you too... but love? I think you're confusing love with infatuation." or something like that. I can't recall it perfectly. I guess there are people who think it's impossible to love with someone unless you know every little detail about them. Go for it, but I suggest not using such strong words.
If she rejects you, I think she would probably say "I hope we can stay friends" anyway, so I never worry about the hurting friendship part. <-- Girls, tell me if I'm wrong there.
I want to know what happens. GOOD LUCK!