Which is not to say the movie doesn't have emotion. As Adam, Gordon-Levitt gives a nice, sensitive performance that captures his inability to understand what's happening to him. And as Adam's mother, Anjelica Houston gives a brief but realistic performance that avoids cliche. But Rogen, real and awkward though his experience may have been, is a bit much. I found him overbearing and unfunny. Given that there's a lot of Rogen in the film, that's a real shame, because Gordon-Levitt's quieter and more restrained performance is just about the polar opposite. (Anna Kendrick also costars as Adam's barely-out-of-med-school therapist.)
No tears are shed and Adam does beat the odds (no spoiler there; Will did write the movie, after all), but thanks to Rogen, the movie unfortunately remains a bit unwell. So I'm just going to give 50/50 a B.