New biome implementation

[irbork]

As stated in FFF:

Everything in the following picture except inserters is in high resolution. The high resolution terrain integration is still in progress, so it won't make it to 0.15 right away.

I plan to put a lot of hours into my 0.15 base and i want it to be in a new biome. Therefore my questions:
1) is new desert going to spawn on current saves like uranium did? If yes, will it be easy to predict - on borers of desert biomes etc.?
2) will it be implemented on the very beginning of 0.15.x or at the very last?
3) should i wait for it or start playing now (more than one month of waiting)?

[Neemys]

1) If dev follow the way they do before, new terrain will only appear on new discovered chunk, no existing one. It will also not follow old biome, so they will be ugly separation between old chunk and new ones.