Beautiful. A few configuration options would be nice (size, speed and number of snowflakes, colour cycling options for the background etc.), but the defaults are nice and, as it stands, this is certainly the best-looking snowy screensaver I've seen so far. The snowflakes look particularly delightful, and the animation is very smooth. It'd be nice if the background colours could be chosen by the user, as I don't like one colour to remain static on the screen for too long in a screensaver, and if the background colour could start off in different shades depending on the time of day, that would be a nice touch.
For a version 1.0, though, this is really very nice indeed.