Assuming it isn't killing your pockets to hold it.

I've got the same issue with a property. I should've sold it at the peak but I turned it into a rental and I've had to supplement it ever since the meltdown. I should be nearly at break even with the next lease. It'll be 5-10 more before I'd have paid it down to be able to sell it though.

If things ever get dire, I'll give it back to the bank. In the mean time, the paper (and real, for a little while longer) losses help shelter some income come tax time.