I’ve just heard back from the folks at MTV.com, who’ve explained what they’re up to with MTV Music, the nifty video archive site they quietly rolled out yesterday.

The answer: They really haven’t rolled out the site. And, in fact, they don’t ever really plan to do so–it’s not really supposed to be something that regular Web surfers are meant to use.

Confused? So am I: After all, MTV Music has a nice, clean design, lots and lots of easy-to-access archival clips (MediaMemo just lost 30 minutes digging through the De La Soul collection).

So why build that unless you wanted everyone to see it?

MTV.com spokesman Tom Biro tried to explain, and if I understand him correctly, the site is supposed to be used as a sort of white-label archive that can be used both by MTV Networks, owned by Viacom (VIA), to build other video sites, as well as outsiders, both professionals and amateurs.

MediaMemo, for instance, might want to build its own De La Soul fan site, and could grab all the clips needed from the MTV site.

That also explains why the site has such a nice clean, look: There aren’t any ads there, because MTV isn’t selling it as a destination site.

Presumably, though, MTV will one day find a way to insert advertising into the clips, so visitors to my De La Soul site will generate some revenue for the network.

In the meantime, you can see this golden oldie, which I remember from, um, high school, without having to view a single ad.

Kudos to our sharp-eyed former coworker, Dan Frommer, who has spotted what appears to be a nice new rollout at MTV.com: a place where you can–gasp!–watch a bunch of videos.

MTV Music seems to be what MTV.com famously should have had, but never really figured out how to do very well (actually, it’s one of several things, but that’s a longer story).

But it’s nice to see it now, regardless: clean interface, embeddable videos, social networky without actually trying to be a social-networking site.

Dan is calling this a “Hulu For Music Videos,” but that’s not the case, at least not formally. Hulu, you may recall, is an actual joint venture between GE (GE) unit NBC and News Corp.’s Fox (NWS), created in large part as a foil against YouTube, owned by Google (GOOG). (News Corp. is the owner of Dow Jones and this Web site.)

But the labels aren’t taking stakes in this site–MTV is just using the existing licenses in a smart way.

We’ve lobbed in calls to MTV and will report back if there’s more to say. But for now we can tell you that the site does have content from all four majors: Warner Music Group (WMG), Sony (SNE), EMI Music Group and Universal Music Group.

It does not have the video for the Killer’s new song, “Human,” which we can find on YouTube, though.

So we’ve asked our neighbor at Starbucks to pick a clip, and he’s taking responsibility for this one, which quite frankly, we’re sick of.

Enjoy: