Originally Posted by Justibone
Wine yeast will make for a "cleaner" taste, and the flavor will be more reproducible. It will also make for higher alcohol content.
I would say that the reproducible part it true. There are countless varieties of wild yeast out there, some of which have been isolated and are now available for sale. You could end up with yeast that are very similar ones in a packet with out adding them. Or you could end up with ones that make something resembling paint thinner.
As far as alcohol content; wilds often can chew through a lot of sugar. Remember that you don't have a mono culture of yeast, like with sterilized grape juice and a yeast packet. So there are yeasts that will act in various ways. Some will eat fast and sink after 5% abv, others will slowly chew away every last molecule resembling sugar. Your results are impossible to predict, and you won't be able to reproduce them... but you can try: if you save the yeast cake you could add new grapes to it. (see sticky on beer yeast forum call: washing yeast, or something like that)