I hate to see Pujols go but from a business point of view the Cardinals were already offering to overpay him to let him become the next Stan Musial for St. Louis. Pujols decided the cash was worth more than that. Maybe not the next two or three years, but in the long run this is probably better for the Cardinals as a team. Two years ago Pujols had a WAR (Wins Above Replacement) of 7.5, last year was 5.1. So, all we have to do is add another 8 wins a year with the $22m a year we aren't going to be paying him to be doing better as a team.
I'll wish Pujols luck, but I probably won't be cheering for Pujols for a while (I won't be booing him either though). Come World Series time if the Angels are in the World Series, I'll still root for the National League unless it is the Cubs then it would be a tough call. In general regardless of who makes the WS, I root for the NL because I don't like the DH.