The primary benefit this technology offers is cost.
For example, let's suppose you move into an older building which was never wired for a lot of phones (a warehouse for example). You have something like 4 analog phone lines running into the facility, not nearly enough for your intended use of the space. Each of those 4 analog lines can be reconfigured as a DSL line. Assume the building is relatively far from the central office, so you can't get the highest speed, and have to settle for 384 K per line. By converting all 4 analog lines to 384 K DSL lines, you would have a total of 1.5 megabits of data carrying capacity, enough to carry 24 simultaneous phone calls while still leaving plenty of room for high-speed internet access. Plus, you can do this without rewiring the building, an important consideration both for you, and for the carrier providing the service.
The real benefit for users is choice, and therefore price.
* All pricings are yet to be determined by ICCC