Less maps included with UT on disc... shitty... however, I doubt they wouldn't include those maps as DL content.
Who's to say that Microsoft doesn't enable the HD-DVD to run games on HD-DVDs in the future.
They've "said" that HD-DVD drive is for movie playback only. They also said that the 360 wouldn't have HDMI - look where we are now. Elite and now the PRO SKU's at Best Buy.
It's only a matter of time before they change their mind.