Ok let me tell you this... If you're making a spag bog its fine doesn't matter at all...

If you're making coq au vin or a Jus IT DOES MATTER!

IMO if you wouldn't drink it then you don't cook with it. There is no such thing as cooking wine unless you are talking about xaoxing wine (Chinese cooking wine).

And the type of wine you use matters too.

Here is a list that would help:

Young, full bodied red wine - Red meat, red meat dishes

Young, full bodied, robust red wine - Red sauces

Earthy red, full bodied red wine - Soups with root vegetables and/or beef stock

Dry white wine or dry fortified wine - Fish/shellfish/seafood, poultry, pork, veal

Dry white wine or dry fortified wine - Light/cream sauces

Crisp, dry white wine - Seafood soups, bouillabaisse

Sweet white wine or sweet fortified wine - Sweet desserts

Dry, fortified wine (i.e.: sherry) - Consomm?, poultry, vegetable soups

Regional cuisine - Regional wine
And I have been known to use dry sherry in place of white wine in cream sauce, or champagne in place of white wine for fish... but don't go overboard either don't use something you need to decanter so nothing older than 3-5 years... IMO anyway.