I just compiled a personal collection of errata of the 2005 paperback edition(pdf file at the bottom of my webpage). I found almost no typos in Volume 1 but quite a bit in Volume 2, and I'm only halfway reading Volume 2. I hope to see answers that make the errata more complete. In addition to typos kind of mistakes, you are more than welcomed to show where Weinberg "cheats" the readers, for example, claims to have derived something but forgets to mention some subtle assumptions that slipped in.