Do we really need demos? This is what the bajillion gaming sites with videos, pictures, previews and reviews are for. Demos are an archaic remnant of days past. You found game demos loaded on the game you bought and they were there in an attempt to get you to buy more games.
Seriously, demos? Who cares and who in their sane mind would pay for a demo? The only way I could see paying for a demo working is if the money you put towards a demo was a deposit towards the actual game itself.
On the other hand, I fully support Betas. Beta testing is the coolest thing in the world, and I wish more companies would embrace public beta testing. Go Blizzard!
Demos....LOL. This is why I torrent stuff.
Edit: Also, screw EA.