It's "snowy" because it's dematerialising. And it's a very high quality image with a pixellation effect deliberately overlaid. Do try to remember that this won't be seen at these dimensions. THe actual logo is mainly seen at a much smaller size.
If you're clicking this image to go through and look at it at the file:TardisDataCore1.png page, you're seeing it at a much larger size than intended.
Also, remember that I can't just use any old font off the internet. For legal reasons, it's gotta be something that's free/public domain/CC-BY-SA.
I'll provide a few more variations, but please be mindful of the limitations when trying to assess these logos.