Personally, I don't mind whether people make funny or informative commentary, as long as it remains an optional thing. If commentary (by the author) was to be added in the actual video (like commentated Let's Plays on YouTube for example) as opposed to in a different (mp3) file, then I would disagree with entertaining commentaries as opposed to informative commentaries.
On the same note, I wouldn't mind seeing multiple commentaries for the same runs (assuming that more than one person / group of people somehow were interested to do that, were it to happen), if one was mostly informative, and one was more entertaining.
For an entertaining commentary, you don't really need to prepare anything special. But for an informative commentary, it is particularly important to gather a lot of information ahead of time, reading the author's submission notes, the game topic and strategies applied, possibly adding information on previous strategies or ideas, and so on. In that regard, NapstrPSX's commentary of Halamantariel/Nitrodon's Earthbound TAS was amazing, because on top of that, he also added a lot of his own experiences with the game, as well as general, interesting information about the game that wasn't shown in the actual run. A shame that run was obsoleted.
So anyway, I think that both kinds of commentaries should be accepted. I mean, if someone wants to make an entertaining commentary, chances are that person wouldn't bother making an informative one, so the run would have no commentary at all. Rather have one commentary which is good for a lot of people, than no commentary at all, right? After all, it's an optional feature when downloading a run, so it's not like someone who doesn't like an entertaining-oriented commentary is forced to listen to it.
However, I think that it should be specified, when linking to a commentary, whether it's more oriented at being informative or entertaining.
