At the title queries. Will there ever be a downloadable Mac version? Or is it too complex to port over to OS X (since the original was only for Mac OS 9)

Also, DX:IW never came out for Mac at all, would the sequel have any chance?

It's a possibility. GOG has been using WINE for some ports, and I've gotten Deus Ex to work in WINE.

Any respond from a GOG staff?

I would certainly love to see a Mac installer!

I've managed to get it working using a Wine bottle, something I managed to do with System Shock 2 as well, but going back and installing System Shock 2 using the new GOG mac installer, I quickly realized GOG did a much better job of ironing out all the issues I had experienced.

Needless to say, I would love to see a Deus Ex mac installer because I am certain GOG can bottle the game better than I ever would be able to.

I would like that very much as well. I want GoG to release a Mac version of Deus Ex in the near future.

As Deus Ex is listed as "Mac Friendly" in rampancy's GOGmix so why not give it a try with Wineskin?

EDIT: You can find a step-by-step explanation here!

I haven't had any luck with any of the emulators so far. And if they were able to get games like System Shock 2, or the Twinsen games (Relentless and Twinsen's Odyssey - which never had a Mac version before) to work, I would hope Deus Ex would get the same treatment... Eventually.