I use Sonos but you can't be completely wireless unless you have speakers with batteries or run low power off a laptop. Ultimately a power source is necessary to drive the speakers.
Sonos does have 'wireless' speakers for streaming audio which are easily placeable anywhere with a power cable. You still need the base Sonos units for streaming. http://www.sonos.com/shop/products/play3
Knowing Denon, though, it'll also cost twice as much.
I don't know what the price is ken, but I believe that competition is good and sono's is way over priced because their are no contenders. But if Denon is just coming in to take some of the cream off the top then nothing will be gained. Look at smart phones, 800 bux for a stupid cell phone,but they are coming down now that others are creating competition.