update: I kinda realized that Bluray players uses optical cables for mulitchannel output. eh since one optical input lang ang receiver ko.... it would seem damay pala sa upgrade to bluray ang AV receiver :'( :'( :'(
hmmm. sir ment, i think bluray players uses its hdmi to output both video and audio (be it run of the mill multichannel sound like dts or dolby or the newer hidef audio like dts ma or dolby hd). that's what makes this generation's cabling a little bit simple, one hdmi cable for both video and audio.
but what makes everything complicated are the old gears that we have or new gears that dont have the 1.3a and above hdmi protocol built in. for nmts, you may need a coax or optical cable to get the both dts and dolby out since its hdmi is for video only.
but i think your connection is hdmi directly to panel then optical/coax from player (xbox or bluray) to receiver. if you do upgrade to a new avr, all you will need are 3 hdmi cable. 1 for bluray (into the avr), 1 for the xbox / xde (into the avr) and 1 for the avr (out to the panel) and you are set for both audio and video. but if you will add an nmt to the mix, another hdmi cable (into the avr) and an optical / coax for sound.
goodluck on your chosen path sir ment.