I just saw 16 blocks. I enjoyed it.
There was an alternate ending that was somewhat more depressing. I’m torn by it. Usually I like endings that aren’t Hollywood; Where the hero fails and/or dies. But still, I preferred the theatrical ending.
There was one revealing mistake I saw. Although the movie was set in New York, there was a sign indicating “Centre street” (note the spelling). That, and the bottle of Canadian Club, helped indicate a Toronto shooting location.