ESPN has an article on the Packers set to retire Favre's #4 number. Interesting read, with the link for those interested.
Here is a quote, that I feel is the best line of the entire article:
Green Bay Packers president and CEO Mark Murphy said Wednesday the team one day will retire Brett Favre's No. 4 jersey, but the team will wait a few years to make sure the quarterback is retired for good this time.