Well, I received my system today a day early!
First impression: Dang, that is a big box, big subwoofer, big receiver, and big speakers.
I currently have it setup with the included wires while I am running 16 gauge through my walls.
I did a firmware update as soon as I powered it up, very smooth and simple process. Firmware can be found here:
Onkyo website. Via USB, it took about 10min.
I had already ordered the Rosewill rnx-n150 wireless adapter, and it is working great with my home network; Pandora is streaming right now!
Overall, the sound so far is FANTASTIC. This system is replacing a 3 year old Samsung blu-ray home theater that came from Best Buy. The big sub really adds a new dimension for me, because I can actually FEEL the bass, even when it isn't loud. My home theater room is 12'x20', and this system fills the room with clear, even sound, even before calibration. The HDMI passthrough is awesome for me since I have an Optoma projector with no audio out, and now I only need ONE cable running to it other than power!
Overall, I am EXTREMELY pleased with everything so far! If you're on the fence about this thing, GO FOR IT!