I won't throw a fit if he is let go. Someone mentioned keeping him for half a season next year, then trading him for a player at the deadline. I think the Sox are okay on money, that might be the best thing to do if he continues to hit HR.
If you are a believer that hitting is contagious, I think you have to believe Adam Dunn is a deadly virus. The Sox need to move on from him long term, and any thought of acquiring a hitter like him for market value again.