[Morgeruat]

they're both servants of deities of the upper(uppity) planes, my monster manual (planescape appendix is stil in the car form gaming last week or I'd bring it up and write out their stats, basically tho Planetars are just a higher level of angel, like a chasme (one of the weakest demons (tannar'ri)) versus the Balor, or Glabrezu, both are so much more powerful than the piddly chasme it's not even funny. maybe Memnoch will post their stats if he isn't deep in the NWN forum (not that I can talk with the amount of time I spend over there.)