Oblivion has rendering errors in the menu (white boxes). Also the status/action bar isn't drawn correctly (both with fbo). Should I file a bug?
Yes, file bugs please. I think I have Oblivion here somewhere, this should be easier to debug than Morrowind.
Note that it will be a while before I send another version of this. I did some benchmarking, and there isn't much of a performance improvement. In most cases the replacement pipeline is slower. We still need it some day, so I'll continue the work, but this makes it less of a priority. I also think that we can improve the performance quite a bit, but it will need quite a bit more work.