For them as wants to know:
The vinegar pie was quite interesting. It did cook up nicely, and my meringue browned prettily and puffed up, though after two days in the fridge it beaded and fell. As MrsDrP remarked, it was somewhat like a lemon pie, without the lemon. (Mine held together very nicely and sliced well -- maybe it was the extra refrigeration?) It did have a pronounced vinegar tang that turned off many of my tasters, though Darwin was actually a big fan of it. (He's not really into sweetness, flavorwise.) But the meringue was popular, if not aesthetically perfect.
I can't say that I'd necessarily make it again, though I'm glad I tried it once. I think I'd rather have a lemon pie -- I think the flavors balance out much better there. But if you were living in the woods of Wisconsin 130 years ago and didn't have lemons available, this is a fairly close facsimile. Try it once, just to say you've had vinegar pie like Ma Ingalls made in the Big Woods. Then be glad you live in 2005.