Not any HDMI will do... you must have HDMI version 1.3 on the player and the processor as that adds throughput support for the new formats:
DTS-HD lossy and Master Audio Lossless, Dolby TrueHD lossless, and Dolby Digital Plus lossy.
Also, your surround processor and its processing engine must be able to use DSP overlay modes (like Dolby Prologic IIx, Logic7, DD-EX, DTS-ES, etc.) at a full 24/192 resolution on all channels as the new formats are capable of sending that kind of sound out depending on the studio or music label.
Why would you want it to downconvert your audio if it doesn't have the processing muscle?
There are many more attributes you want to look at when this new equipment arrives.
What's wrong with using the *player's* built-in processors? O.K. so you'll need 3 or 4 pairs of analog cables - no biggy. Now you get to keep your original receiver.
Why "must" one use these modes? Personally I don't like them as most sound gimmicky to me and anyway, they disturb the movie director's intentions.
how can HDMI 1.3 equipment be shippin when HDMI 1.3 spec hasn't been officially approved? according to hdmi.org, only 1.2a has been approved and that was last october!