I'd give them a B. The Wii U announcement was standard affair. I wasn't expecting any major game announcements. They unveiled the console and controller. On that front, things seem good for the most part besides the possible one screen controller per console thing. That decision would be a major failure in otherwise strong hardware.
Anyway, Nintendo lost major points for announcing next to NOTHING for Wii except Zelda. That hurts. Also, the 3DS lineup wasn't especially thrilling. They're all console games that don't particularly play on the strengths of the 3DS. DS had unique games and traditional games. I'm waiting for Nintendo to give me a reason to really, really, really want to buy 3DS for its originality rather than wanting to buy it eventually because I buy all hardware eventually.