Absolutely, a great idea. I love Bruma and it would be a cool way to tie Skyrim together with Oblivion the where you would revisit the same houses (and maybe even people, those who are still alive) from one small part of the last game. It won't happen though.
With the possible exception of the elven residents of Bruma, I doubt any characters you saw in it in Oblivion would be alive, even if it did appear in Skyrim.
And I doubt we'll see it, for one thing, the game takes place in Skyrim, and Bruma is part of Cyrodiil. This doesn't mean much on its own as the borders of the provinces could well have shifted during the 2oo years between games. But when you consider that there are supposed to be five major cities, less than the lore describes, I rather doubt it. If Bethesda already has to remove cities that are part of province in known lore, I doubt they'd add in ones that weren't originally supposed to be in Skyrim.
I'm not sure I'd want to see Bruma either, for the same reasons I wouldn't want to see Solstheim, I've already seen Bruma in Oblivion, and when I play a new game, I want to see new places I've never seen before, not old ones. Nostalgic value aside, since this is the first time since Arena we've been able to go to Skyrim in any game, it's a perfect oportunity to show us some new things, so I wouldn't want them to spend time remaking old places, even though Bruma could end up looking pretty different with two centuries between games and a new engine.
In any case, I would not be surprised if there will eventually be a mod adding Bruma and the surrounding area, if the game supports mods.