It looks like the “cheaper” version of the Xbox 360 will end up depriving users of it more than just features It seems that some future 360 games will require hard drives, something that only the more expensive version of the console touts by default. The example giving is Sports Interactive's “Worldwide Soccer Manager 2006”, which will only be playable on the hard-drive equipped Xbox 360. Future titles face this possibility as well, such as Final Fantasy XI.
The article expresses doubt that the lack of a few titles on one version of the console probably won't affect many, and that's probably right, though one must wonder how much of this was predicted. As games get larger and more complex, however, the necessity of a hard drive will probably increase exponentially, and we could see a lot of backlash due to this in the future.