I probably had a better experience watching this film than most will, because I saw it with a friend of mine who is a real birder, so seeing his reaction to it all was priceless. That may have covered up some of the flaws and made it far more enjoyable.
But The Big Year is a perfectly... fine ... movie. It has plenty of exposition, many cheap transitions, a few bad flashbacks, some bad narraration, and even more of all four of these things in the extended edition.
It's never revolutionary or incredible, but I found myself having a good time, getting some laughs, and to my surprise even caring about all three lead characters. I enjoyed the character arcs of all three of them even though they weren't super smartly written and were somewhat predictable.
It's flawed, not as good or smart as it could be, but I still had a good time.