Can't wait to see pictures of future bitcoin mining rigs when these are out en masse. Hundreds of USB hubs connected to one another. (if that would even work I dont know)
Unlikely that someone would opt for that - except for fun. The USB miner is for "opportunistic" mining, where you exploit the availability of free power, e.g. sitting in starbucks, drinking a coffee. In the grand scheme of things, this of course is a form of leeching and is probably only interesting to people who are tight on budget. Also at current BTC rates the USB miner will generate around 0.07 USD per hour. So unless BTC prices hit $10,000, it's probably not worth the effort.
For me, the interesting aspect is the size factor, for promoting and educating others. Call it the "printing press which fits into your pocket".