Umm, each to his own. I'll probably go for it and get my daughter in NYC to pop it in a jiffy bag to post. I think it would be useful for charging whilst viewing films in landscape orientation and outputting audio without fannying around with bluetooth. If the N7's own micro USB socket is simultaneously available for an OTG cable and flash drive, even better.
Incredibly, or not, it'll only be the second official Asus accessory produced since the N7 was released half a year back.
YMMV.