The Sigma SMP8910 is supposed to be the first Sigma players that can handle Blu-ray 3D. My guess though you won't see these players start to hit until at some point mid 2012
As far as the Xtreamer Prodigy I would personally wait until 3rd parties confirm it supports Blu-ray 3D
Also, there is no guarantee that the SMP8910 players will come with Cinavia. Cinavia is required for commercial blu-ray players. This does apply to media players that cannot function as a commercial blu-ray player (i.e. play back a physical disc via a ROM drive)