constance, from what i've learned, that is a pretty basic style from provence, which allows for lots of substitutions. if you like marsala, go for it and let us know the results. in fact, depending on the gaminess of the vennison, or lack thereof actually, it might even work better.
the first time i made this, with lamb neck and shoulders, i used a merlot. it was good, but i found white wine works better with strongly flavored lamb. i used a nice italian pinot grigio delle venezie, and the citrus was oranges, as the original recipe suggests (from "les halles") and it came out great.
also, don't go nuts with the herbs de provence. a few fresh herbs tied into a bundle, like a few sprigs of thyme or rosemary, a few bay leaves, and a small bunch of parsley is all you need, and better than the 8 or 10 herb combos that often make up dried or powdered herbs de provence blend.
they're ok, but fresh is better, imo.
btw, robo, the stew comes out best if you use cuts of meat like shoulder chops and neck chunks, including the bones. the marrow and other gelatin that comes out of the bones makes the stew thick, and hearty. and sucking on the neck cartelidge soothes the savage breast.
A true lover of nature does not despair now that his mistress has turned a colder cheek.