Yea, I think anime and VOCALOID songs are most likely to be covered. (Especially on Nico Nico Douga because it's more VOCALOID/anime oriented I think.) However there are artists who also do other genres. See Teppei Sensei.
"Ensoushitemita" itself literally just means "tried to do a musical performance". So wether it's VOCALOID, anime etc is not included in that term.
Plus some artist may majorly play songs of a certain genre but at times do forays into others. (E.g. an artist who does VOCALOID covers tries to do a cover of a ORDER MADE song, because they like them.)
So in short. I think if it's applicable we could categorize the content, but right now, there doesn't seem such need. (Since the wiki is still rather small and needs further elaboration.)
And with cite information I meant linking to where the artist him/herself stated. e.g. on blog/account profiles or tweets.
I'm not quite sure what kind of information you'd like to cite on YouTube?
If the artist doesn't want unauthorized reprints, we shouldn't link to them on YouTube either. And if the artist himself has an official account, I guess it's pretty safe to link to them.
OMG this is a great word play based on wrong punctuation
I don't quite get what you mean. I suppose you mean which informations the artist wants to be revealed and whatnot?
I think the important thing is to cite information. When the artist him/herself stated something, I don't see any point in not mentioning it, unless he/she stated not to reveal so (E.g. something like "please don't reveal by real name" etc.)
So as a rule of thumb as long as one can prove the source and as long as it's a "public" source, it's fine to include. Exceptions may arise. Also as far as I know that's how it's handled on the Utaite wiki.