No I don't. They don't make a whole lot of sense in terms of their own lore and ideals set against the Horde and Alliance.
The whole Houjin vs Tushui thing is the main problem. They are both highly disciplined and although they have differing ideals, they still work together and get along. How do they go from that to fighting and killing in the name of the two warmongering kings of the Alliance and Horde? I don't buy the whole "oh they spar but don't kill each other" thing either. Why would Varian or Garrosh have any use for soldiers that would leave their enemies intact in a time of war?
They also haven't had much influence on anything. They appear to be mostly inept and require us with our leaders to clean up their mess. The only Pandaren with any degree of competence are the Shado-pan. What even happened to the characters introduced to us in the start zone? I don't recall even seeing Ji or Aysa between 85 and 90.
Moving on from Mists, we'll obviously be seeing less of them and my guess is they'll essentially become Draenei/Blood Elf 2.0 and be forgotten for the next 3 expansions.
In other terms though I think they are certainly the prettiest race Blizzard has created, and I can only hope the new models in future get as much love and care put into them.
If Blizzard wants to do Neutral it should be either a third faction (which will obviously require an overhaul of some systems though not all that much; some new 3-way BGs might be cool, but existing 1v1 can work by simply matchmaking Alliance vs X or Horde, Horde vs X or Alliance. Doesn't need to make sense in lore, we do after all have Pandaren, Worgen and Goblins fighting in WSG and AV)
OR they should do it with a race that is actually known for warmongering and being bastards with many warring "sub-factions". Goblins could have been a good candidate; the cartels always fight one another and they're known for selling their services. This is the main thing Pandas are missing IMO. They aren't a warlike people, so why would they join two factions that would force them to fight one another?