I watched a big part of the LP, and I gotta say, you have very good SMB skills, but your commentary doesn't really add much to the videos. I like watching someone being skilled at a game, but if that means he is silent and concentrated most of the time, there's really no need to record your voice along with it. Or you can add commentary afterwards, that's no crime either.

Therefore, I think you should just call the videos a '106% run' rather than a Let's Play.
Another debatable point in LPing 'difficult' games is that if you do record your voice live, most of the commentary will come down to 'oh darn I messed up' because that is the natural reaction to seeing your own failure

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Now unlike some others in this thread, I understand that coming up with 'good' commentary is pretty hard, especially for a game that's so ridiculously overdone in such a short amount of time it's not even funny anymore.

So my advice: watch some other LPers and some less popular games, see what they like to talk about and let yourself be inspired by them. You shouldn't copy them, but you should at least choose some sort of direction for your videos, that is if you want to talk over them.