TS and m2t formats are very common MPEG2 extensions. TS is the Mpeg2 recording format of HD TV in France and several countries. It also is a format for TV on Internet (Freebox). M2T is a format of HD camcorder outputing Mpeg2. So this would be nice to add these format by default to Mediatomb or several people are going to complain and report bugs.
The following worked for me:
<map from="ts" to="video/mp2t"/>
<map from="m2t" to="video/mp2t"/>