Out of curiosity, does anyone know if any of the Linux Ubuntu supporting games from GOG run on Steam OS, or what kind of partial compatibility problems might arise?

Kinda debating on getting a Steambox as I have a Steam account too but the fact that it won't support all my games is a bummer; course getting some gaming for half what it would cost me to build the proper uber-tower I'd want to build might be worth it. Currently, all I have is a lower-end smart phone and tablet and the Chromebook I'm typing this post on. No proper gaming is starting to get to me...

Personally i'd build my own rig (and i did for $525).

As for if any GoG games would work on the SteamOS, i want to say maybe? In theory they could work. With Ubuntu you're mostly looking at a guaranteed package set and running under XWindows, so as long as the dependencies are working, it supports the architecture (I've tried testing with a 64bit linux distro that didn't support 32bit applications), and it can extract the package (assuming it's more than .tgz or .tbz2 or tar.xz or something), then i'd think it would work.

Steam OS is a variant of the Debian OS, and... ummm... i don't know.

The real problems is package dependencies. With ubuntu, it's pretty much guaranteed that gog's games will run. Steam os, I never use it. But to my knowledge it's based on debian. And debian prefers old but stable package over new but not yet proven that ubuntu provides.

I think you should choose which steambox you want, see the specs, and try to findout how much it cost of you build it ypurself. If the price is acceptable, go that route. As for os you can't go wrong with ubuntu, as it is supported officially by both steam and gog

Why don't you just build your own pc and install Ubuntu/Linux Mint on it an install the Steam Linux client. That would be much cheaper and give you better specs then what you get with a store bundled pc or Steam box. All the games that run on Steam OS will run on Ubuntu/Linux Mint.

As others have pointed out, there is no point in specifically installing SteamOS.
That's really just meant as an easy way for developers to put out 'Steam machines'.
You can just install Linux and make the Steam client start in big picture mode if you want.

GO GET IT! They're incredible, so I've heard.
No joke. Your GOG games will run fine, and will be loaded even better once Galaxy's up. Plus, dat controller... it surely would be nice to test some (gog games) slow paced/fps/racing titles with that! ;P

And oh, Ubuntu: versatile. SteamOS is for the living room. Pick your poison and have fun! :)