According to some sources the Oblivion release date has been pushed back to December 5th, and 2K Games (the publishers for Oblivion) have confirmed this. Personally I'm wondering how you're able to push back a release date that never existed. Last I heard the release date was "Holiday's 2005". December 5th would be in the "Holiday's 2005" bracket and therefore there's no news here.
To be honest I'm finding this lack of information being released by Bethesda a little tedious. I was around for Morrowind's release with the similarly little-PR pre-launch, and that was just as irritating.
Obviously the guys at Bethesda aren't morons who don't know what they're doing, but I'm blown if I personally know what they're doing.
Ho-hum.