well, i know there is advice to freeze unused wine in ice cube trays, to use in cooking, and i've accidentally frozen part of a bottle of wine by putting it in the freezer to chill it quicker and then forgotten about it (maybe like you've done). the wine was fine, although it was only the bit in the neck that had actually frozen.
perhaps for wine buffs, it would be a no-no as it may alter the taste, but i'd give it a go and see what you think. i'm sure it would be safe to drink.