Last month's question - "Will DT Throttle DSL Speeds for Exceeding Quota?" (here) has been answered: Yes.
Deutsche Telekom announced quota limits on its fixed service, with speed reduction penalty (or top-up option). Nevertheless, it excludes its own video and voice services - and explains why it does not violate Neutrality.
"Given the rapid growth of data .. As of 2 May 2013, a monthly quota of 75GB will apply for ‘Call & Surf’ plans with a download connection speed of up to 16Mbps, 200GB for speeds of up to 50Mbps, 300GB for up to 100Mbps and 400GB for packages with a connection of up to 200Mbps .. If the volume limit is reached, a uniform reduction in Internet bandwidth to 384 Kbit/s will be applied"
Michael Hagspihl (pictured), Marketing Director, explained that "Users of "Entertain" service will not count against the volume contained in the tariff .. so we are sure that they will not suddenly sit in front of a black screen .. Also Voice over the telecom connection is not counted .. Both services are, unlike Internet services, managed services that are produced in a high quality and secure and paid for separately by the customer. Regular Internet services are not subject to discrimination by the "best-effort" principle - offering as much as possible with the resources available".
See "Telekom ändert Tarifstruktur fürs Festnetz" ("Telecom tariff structure changes for the fixed network") - here.