I just finished watching the John Adama miniseries on HBO (I had dvr’ed it). If you didn’t get to see it, I commend it to you. I haven’t read McCullough’s book and I’ll confess that I was never much of an Adams guy (tending toward Jefferson). So I can’t independently vouch for its accuracy. I can vouch for its entertainment value, however–I thought it was really well done, compelling viewing. My wife, who generally has little patience for historical programs of this sort, also found it mightily entertaining. I was especially impressed with how they brought to life the debates of the age, presenting viewpoints sympathetically and identifying the clash of positions. The episode on the Declaration of Independence was really well-done I think, and in particular, I learned a lot about the concerns of those opposed to independence.
I’m sure there are many of you out there who know much more about this than I do, so I just pass along my opinion as a viewer with a casual interest in the subject matter.