new features introduced in onkyo 2012 models:
* MHL (mobile HDMI link)
* InstaPrevue
* some GUI enhancements
* improved standby operation (reduced power consumption when using HDMI-through, network standby giving ability to switch the receiver on via remote app ala Wake-On-LAN)
if any of the features above are must-haves for you then i suggest holding out for the 616, otherwise either way will be great. street price for both is quite the same so you won't really save much with 609. if you go with the older model, it would be for the reason that it currently has a more mature firmware.