Interesting. One good friend of mine is an EnFP, and we get along well - she's so adorable! But I have a sneaking suspicion if I was to be cooped up with her for too long, we'd get on each other's nerves very quickly.
I didn't think she was an ENFP at first - she definitely didn't strike me as OMG that's ME! But now that I'm paying attention, she does deal with things and react in similar ways to me. So it's subtle, but naturally a type is going to look differently to you from the outside as opposed to 'the inside'. :P
And I think a friend I used to know over the internet was, in retrospect, quite a strong ENFP. Possibly ENFJ. Incredibly charismatic, childlike in his joy for some things, always finding totally irrelevant things to comment about and make interesting, chatty and friendly, but still a bit shy and insecure when it came down to it.