Day one! With my kids of course! But hell, it looks so good I'd probably end up seeing it even if I didn't have little girls :)
I know I'm in the mega minority on this but I tend to like Disney animation more than Pixar movies. Princes and the Frog had some big issues but I enjoyed it much more than the latest Pixar flicks (which had tons of heart but mega story issues for me).
Anyway, this looks great!