I was lucky enough to unload a few at the right time myself. I also felt the dam was going to give way. I, like most, didn't think it would recede to the level it did. I figured I needed a place to live and I don't like moving that much.
That decision cost me a cool 200k. My primary here was up to nearly 500k in 2006 and I sold it for 285k in 2010(25k more than I paid in 2003 not including improvements) to move into my current primary. I did have a 15 year note for most of the time so I was able to recover all the equity out of my back pocket and parlay it.
Looking back, I should have sold it when I made the choice to unload some investment properties. The old mentality that you need to own your home was faulty. You never lose on real estate right? Then you have the old adage that you don't default on a debt. I've seen so many people walk away or I've short sold their homes. Another reason to keep a 30 year note. If the **** hits the fan and you are forced to walk away, you aren't walking away from so much capital. I can honestly say I could walk away and not feel bad about it. I wouldn't like the consequences but sometimes it's a business decision.