I got to see this show a few months ago--If I remember right, it wasn't bad--it was nice to see an exhibit there on principle to counter the Eberts of the world, but ... it's really like.. "Baby's First Game Art Exhibit" in a lot of ways.
It dwells much too long on the same popular franchises that show up on the top 10 lists over on IGN. Rather than try and get a little more variety on the floor, there were a dozen iterations of Zelda and Mario. Even Pitfall, Donkey Kong, and Phantasy Star showed up multiple times, rather than using the space for more titles. There were a few random throwback titles, sure...but they felt like they were probably the curator's old favorites or something (Spy vs. Spy the game...? I mean, maybe it was an awesome game, but really?).
It's a nice first step, but it felt to me mostly just like a tool to get people in the museum doors. That said, it was still fun for the excuse to go into DC!