Which Blue Ray player to buy ?

Playstation 3. A no brainer since firmware updates can be on online.

Sony BDPS5000ES is the newest greatest, with good 2 channel audio

Having owned several Blu ray players, I can confidently recommend the Panasonic brand. I currently own the BD35 and it has been excellent. Panasonic is set to release new models shortly, so I'm not sure what the availability is of current models. Also, Oppo is set to release their player in the near future and it should be very good as well, based solely on reputation.

When buying, you need to consider if you have an ethernet connection available (models with ehternet connection are much easier to update the firmware) and if you need 7.1 analog connections (all will offer HDMI). You also need to know if your receiver/processor is capable of decoding the latest audio codecs (true HD and DTS Master) or if you need the player to do it.

Sony, Denon and Pioneer all make high end players, but its not necessary to spend big dollars to get the excellent picture quality of blu-ray.

Thank you Cruz.
I am going to run it throughi my two channel system. My system ( Mcintosh c2200 preamp , Mcintosh mc352 amp & B&W 804 matrix speakers ) does not have a decoder because I use it primarily for audio. I currently have a Marantz DV9550 universal player that I intend to keep. Therefore, the blue ray player would be used exclusively for films. I have heard good things about Oppo and I know they are getting ready to release their blue ray. Panasonic I don't know.
It sounds like I need the unit to have the built in decoder. Any specific recommendations ?