There's a Phillips player that's now been officially withdrawn that'll do the trick.
The only downside is, you can't maximise the screen on the PPC version which makes it useless for viewing full screen ports from Nero.
You will get to see a much reduced rendering of your recode though and I suppose it could keep you going until something better comes along.
Download from here (Under Phillips Mpeg4 Player)
Further info here
Why nothing's available to do this properly from Nero is beyond me.
The software has an output profile for PPC for godssakes!