I found it light, and boring because of how light it was. I had studied Gödel's theorems, etc., so I really could not take the pace for explaining the logic stuff (most of the book) in GEB.
By the way, I would recommend any programmer interested in physics "The Road to Reality" by Penrose. I think that's a very challenging book, that can be interesting for programmers, even if it's not about programming. Compared to that kind of material, GEB is very, very light.