Here's another guy claiming he gets 35wpm by typing with a thumb and his index finger. Personally, we don't see how using the index finger on one side and a thumb on the other helps the typing. Unless of course, he's got a foam rubber thumb on his right hand.
YouTube (see related videos for this one) is filled with these videos now, with people claiming using their two pinkies, an ear and an elbow, an eyeball and some snot, or their genitalia gets them super fast iPhone typing.
Us? We use two thumbs and we're pulling it off, just a day or two into our experience. After a week of practice and training the dictionary, we'll probably be pros.