I feel as though I'm stealing ideas from Zach here, but I have to agree with him here:
Austria's just plain screwed, and they have no chance of ever getting back on their feet ever again...
Prussia could do well, but it would involve them improving internally as an industrial/colonial superpower...
The German Confederation/Confederation of the Rhine will be the major place of German nationalism, and the most powerful German state is going to be Westphalia (which is ruled by family of Napoleon, and therefore Napoleon's lapdog in Europe...) or Bavaria (which has years of tradition and is essentially a non-defeated Austria...)