We've seen that Realtek has wireless USB marchitecture up and running and we can tell you that it works. The protocol itself supports up to 20 feet cca. 6 meter range and it is set to replace quite a few cables.
It won't compete with WiFi due to its range limitations and the first devices that will be out by the end of the year might cost up to $200 for a receiver and sender part.
You lose the cable but you still have to plug one antenna sender in your PC while the second receiver antenna part is plugged into your printer.
The current price won't live that long, as $200 is way to much for any kind of connection including a wireless one.