Interesting, the idea of anthropological study vs. peer pressure. I like how the episode uses both levels of "life among the gorillas" -- emphasizing what Marshall wants to do with his life and also as a metaphor for what he's doing in Barney's office.
Barney's posters are totally demotivators.com -- only not literally, of course.
Marshall to Ted: "Preserving something that's already gone: That sounds like environmental law."
That we immediately segue from that to Marshall deciding he should preserve his relationship with Lily even at the expense of his relationship with Barney's legal department is a bit doubletake-inducing, though obviously I didn't expect Marshall and Lily to break up over this (wouldn't have even if I didn't know about the episodes that come later).
Also: you don't have to send her care packages, Ted.