WR - I'd be a little cautious about using his choice of an appraiser. Or at least, if you don't agree with the appraisal, insist on getting a second one.
Hey, at least he asked you for permission - some WASs would have just barged in on their own with the appraiser.
(Incidentally, since it's in your interest for the appraisal to come in low, no need to pick up the dirty laundry etc beforehand lol. And be sure to uncover any flaws that you may have been hiding, like a rug over a big stain in the hardwood floors or whatever - remember, this is the OPPOSITE of showing a house to sell it).
What do you have to split in terms of debts, retirement savings accounts, other investments or savings, cars, boats, etc?
Also - I know it's hard, but remember this is just the business side. I know you don't want it (the D) but you need to keep your head and be pro-active about fighting for your fair share.