WD TV Live - Panasonic Viera and Mezzmo

When I will buy a WD TV live and connect it to my tv and Mezzmo, will transcoding still be needed or will WD TV live support all the media offered directly to the tv?

I have a lot of problems now with subs and transcoding...... so if the WD TV live has a broad support for formats transcoding is not necessary anymore?

Depending on your Viera model, the WD TV Live will most likely offer broader format support. The newer Viera models do play more than the older ones, but the WD TV supports more in either case.