None of the popular MP servers cater for NTTR/Normandy. If the 104th, BF, Open conflict, ACG etc ported their missions and server to 2.1 then you would see far more traffic.
As it stands however, its far too much work to do that. So really its only 'single' player servers currently up.
Edit: the 104th have run events in the NTTR map which went down well.