If Howard really does plan on leaving Orlando when he becomes a free agent in the summer of 2012, then the Magic need to seriously consider trading him and getting some value in return for their franchise center.
We've seen teams in the recent past hold off trading their franchise players when they threatened to leave, and pay for it. Toronto is in full on rebuilding mode since Chris Bosh left them and it looks like will be drafting in the top 10 for the next few years.
On the flip side we saw the Denver Nuggets take the initiative and shipped Carmelo Anthony to the Knicks for almost an entire starting lineup and actually improving their team in the short term and creating an opportunity to build a title contender in the long term, without having to suffer through year after year of 25-win seasons.
These scenarios are made up of teams that Howard would sign an extension with, and teams that would have enough pieces to build a trade that Orlando would consider accepting. If a team does not fit both of those criteria then they are not in the race.