Not sure if this is just me or why I haven't seen this mentioned more. Most seeds appear to generate no snow biomes at all for hundreds and hundreds of meters, and as far as I've been able to fly, not at all. I've gone through and created maybe 20 or 25 worlds in a row, flown around for about 500 m in all directions, no snow at all. Plenty of deserts, swamps, extreme hills, etc.
The next thing is, some seeds generate *only* snow ! Seed -9124484053911961482 generates a world that I can keep flying and flying through and its all snow (OK, just tried it, and in the middle of miles of snow was one little 10x10 green patch, but then more snow...if you all try that seed and the snow ends, OK I'm wrong, but you have to admit this seed generates a huge snow area compared to the normal biome size.)
The only seeds I have that generate a mixture of snow and everything else in some reasonable proportion I got off of other postings - my copy of the game has never generated one.
I can appreciate the "mushroom biome", which I've never even seen before, being really rare. But a little more snow would be nice ! at least within 500 meters of somewhere, I can usually see desert/swamp/forest/hills within that range.
yeah that seed is great. I just find it odd that the vast majority of Minecraft players who don't type in a seed and don't follow forums are never even going to know there's snow since it almost never appears.