Apparrently, DVB-T(2) is pretty close to the maximum allowed [according to] Shannon -- so it really just depends on what frequencies are used (and coding details). It is a frequency that is well suited for broadcast ("push") -- so not sure if de-regulating it for general send-receive is such a good idea (see sibling comments). Anyway, did you see:

http://www.satbroadcasts.com/DVB-T_Bitrate_Calculator.html

And:

http://en.wikipedia.org/wiki/DVB-T2#Technical_details

?