There's a Sunday Session podcast on The Brewing Network with Shea Comfort about brewing beers with wine yeasts. The vital lesson that comes out of it: wine yeasts are not bred to handle the same sugars as ale/lager yeasts (and lager yeasts can digest some sugars that ale yeasts can't, for that matter). Namely, wine yeasts (including champagne yeasts) cannot digest maltotriose, which accounts for quite a bit of the complex sugar in wort. The result can be quite a lot of residual sweetness, even when using a champagne yeast. The conventional wisdom that champagne yeast will "dry out" your beer is incorrect.
edit: might be better off with the Super High Gravity Ale yeast - WLP099