Elder Scrolls IV: Xbox 360 HDD recommended?

According to a forum post on the official Elder Scrolls website, Elder Scrolls IV: Oblivion will not require the Xbox 360 hard drive. However, the post adds, "We would recommend you get one if you have the means, but it is in no way a requirement." Interestingly enough, at the time of this Joystiq post, the Elder Scrolls forums could not be accessed for further details [UPDATE: the forum is back online]. So it's unclear why the hard drive was recommended for the game, and it brings into question the limitations of the basic Xbox package, which will lack the 20GB HDD.
Thoughts?