I guess the cable companies just can't allow a natural price advantage work in their favor - with DSL, you have to have a phone line in service, so it's going to cost you at least $16-17 for the basic line in addition to the DSL charge.
I had a house in Old East Dallas (renting it out, now) that has had SBC DSL for ~3.5 years. TCI / AT&T / Comcast have never made cable internet available in most of Dallas, being content to wire all the 'burbs who had separate cable systems prior to the TCI / AT&T buyout, and only wiring a few very large apartment areas & 1 or 2 affluent neighborhoods in Dallas proper.
To this day you can't get any info out of Comcast regarding possible availability dates. Methinks it has something to do with Dallas' cable infrastructure - has to be the last burg in the universe with dual-coax cable. Gonna cost a lotta $$$ to pull the fiber-o, and SBC already has a significant portion of the city covered with DSL, having concentrated their Project Pronto in Dallas a few years ago.
I'd have probably gone with cable in Dallas, had I had the opportunity - the speed dfference is just too great to ignore, for essentially the same price. Gotta admit, tho, wondered many times as my cable TV went down (on a very regular basis) if my inet would have been down as well. Fiber-o would probably help that, but it's gonna be a long time coming in Dallas.
One $$$ savings tip not mentioned yet - if you have cable, and are not married to your land line, ditch the Telco phone line (assuming you can use cellular instead, like so many ppl are doing these days). Little known factoid of the cell phone number portability issue is that it will allow you to change your old home number over to your cellphone......