While ATM is used as a transport technology in backhaul and core networks for UMTS and ADSL today it looks like the technology is pretty much on the way out in next generation networks. In LTE for example, ATM no longer plays a role, everything is specified only down to the IP layer. The technology used below is up to the network operator. In many cases this will be Ethernet over copper (e.g. VDSL), fiber or Ethernet microwave.
Another example is the VDSL deployment of Deutsche Telekom (DT) in Germany. According to heise magazine 22/08, DT uses Ethernet over a Gigabit fibre (802.3ah) to their outdoor VDSL DSLAMs. Ethernet is also used over the last few meters of copper cable to the customer instead of ATM. While the VDSL modems can still do ATM, DT has decided to use Ethernet in combination with VLAN (Virtual LAN) encapsulation (802.1q). At the moment, only VLAN-ID 7 is used for all kinds of data, but there are rumors that DT plans to use several VLAN-IDs to separate IPTV from normal Internet access in the future with their IADs (Integrated Access Devices) that support Internet access, IPTV and (SIP) telephony.