Not only can you use widescreen resolutions in Quake (via the DarkPlaces mod) but using those directions you can add the music soundtracks back in (which aren't included in the Steam versions of Quake 1/2).
I didn't get an email but when I logged into my Battle.net account about an hour ago the Starcraft II beta was added to my games list and I was able to access the client download from there.