Any word on a official high res texture pack?

no

there's plenty of unofficial ones though and they are really good.

Is there even something like an "official" hi-res texture pack? I don't remember any for Oblivion. Hi-res packs are usually mod work, right?

I just go to the official nexus website and download all the high-res textures I want. Works great and the best part is you can pick any combination you want and adapt them to your needs.

Oh, PC version only, of course.