Anybody know if this is coming to the Mac ?

Cannot see anything on their website regarding this though.

The initial release will be for the PC and there will be a Mac version available sometime after release, though I'm not aware of any specific target date for it.

On GOG and afaik all other plattforms, there'll be only a Windows release at first, but since Grimrock 1 was eventually released for Mac and Linux as well, chances are good the same will happen for Grimrock 2. It might take a bit though.
My guess is that running the Windows version on Mac with a Wine wrapper might be tricky, too. The game's requirements state that Shader Model 3.0 has to be supported which can be troublesome under Wine.

Thanks everyone :)

Well, us Mac/Linux players should remember that we were promised a Mac version of Torchlight II... and we never got one.
That thread is kind of vague too: "Yeah, the pre-order will get you the game for any and all possible future versions that we'll sell through our own site." Possible future versions eh? With no specific mention.
I'll keep my money until those possible versions are actually available.

Yep, the thread doesn't give any relevant information about a Mac release. I'd too suggest to wait.

In Almost Human's case, it's reasonable to expect that there'll be one coming. They did post-release porting for LoG1 as well, and that was when their team consisted of four people.