I just bought a PS3 as a player after debating my options. It's the ONLY $400 player that can decode DTS-HD Master Audio.
It is recommended to use the PS3 with a receiver that supports at least 5.1 PCM over HDMI. 7.1 PCM over HDMI for a 7.1 speaker setup.
Sony has released two new players. The cheaper player, $400 player seems like it could be a nice player. It does not decode DTS-HD Master Audio. If you feel you must have that (and you can live without out pretty easily*,) you will need a receiver that decodes DTS-HD Master Audio.
So it depends on whether you want to work with PCM or bitstream. PS3 for PCM; New Sony player for bitstream with a receiver with TrueHD/DTS-HD Master Audio decoding.
You can read more on the endless PCM vs bitstream debate in this sub forum, but be assured both can work very well. There are pros and cons to both methods though.
* If you can't decode DTS-HD Master Audio, your player or receiver can decode the DTS core which is part of the DTS-HD Master Audio soundtrack. This core is usually 1.5 Mb/s and is of very high quality. Some people may not be able to tell it apart from the lossless DTS-HD Master Audio soundtrack