Standalone DVDP do not yet handle MKV & - I've d/l ConvertXtoDVD and it looks good, but one issue is it only converts to DVD5 and not to MPEG4 like Divx/Xvid which is a bit meaningless. The hottest topic of discussion lately has been WDTV which plays a lot of formats which includes MKV too.
Click to - It seems you've not been following the threads here bro.