PS3 is the only player worth buying right now, as it will be upgradeable to profile 2.0
The rest, in my opinion not so much. I had a hard time swallowing the "you need a toy to play movies!" - but it truly is a great little device. Since it's the same price as the standalones, you really cannot lose with it.
Also, of course it supports 5.1 audio, right now. This is the standard dolby digital/DTS you're used to. The firmware update is for uncompressed "HD Audio" which requires a receiver that supports it over HDMI. Mine does not currently, but it's next on the upgrade list
