Being both an OpenMPT developer and ModArchive administrator, I don't see much use for MTPM support right now - Generally we want files on ModArchive to be playable "out of the box", and most of the time, MPTMs would most likely contain VST plugins, which you cannot simply use in a player like XMPlay. However, now that there is actually libopenmpt (and with it, input plugins for foobar, Winamp and XMPlay), it is actually possible now to actually play MPTM files in other programs than OpenMPT (but still without plugins, as said), it is slightly more likely that we could add MPTM support at some point. I'm pretty neutral on this topic though, so someone else on the team might have another opinion.
