It seems a little odd at a time when 3G data services are starting to compete with fixed line ADSL services that T-Mobile in Germany has completed a trial that used ADSL to provide the back haul link for data.
The Register suggests that this technique, but using ADSL2+, may start to be used in the UK. T-Mobile, if it were to employ xDSL services, would hopefully not be using the common £20 to £30 products but rather would be renting business grade low contention services which can cost a few hundred pounds a month for guaranteed low levels of contention.
Mobile providers who are pushing their data services need to be careful to ensure that cost savings do not impact heavily on the quality of service. We are seeing more and more people considering abandoning their fixed line telephone services and subscribing to a 3G data service so the contention on each 3G base station is probably increasing quickly. If the lower cost backhaul leads to more base stations in an area it could, by reducing the number of users on each base station, lead to improvements in signal coverage and better speeds.