The summer sale is forcing me to take the Linux Gamble. I'm predominantly a Linux user, but I buy some windows games that I run in wine. I definitely prefer DRM free, regardless. I've bought four games so far that I know have Linux versions. The gamble is that GOG will give me the Linux version for free once they support Linux.

Either way, I'd still rather have a GOG DRM free version over a steam version.

I wish they would have a "coming soon to linux" tag on the games they planned on releasing as I would buy more (of those) if they did.

There is no guarantee what GOG will in regards with linux - no details basically, so your better off buying the games now unless you want to wait for the next sale (i have zero idea if they will give the linux versions for free -- personally i would say yes )

I'd buy Steamworld Dig and Rogue Legacy in a heartbeat here if I knew the Linuxports are coming.
As it is now, I just hope they'll be in some bundle sometime so I will get all the ports at a good price.

I also use Linux... Linux only, actually.
So I do all my gaming via Wine. Sometimes it is a pain in the a**, but it is worth the effort most of the time. And DRM-free means ownership and ownership means freedom, which is good, is it not?
I support GOG.com and buy my games here and also hope there will be Linux support in a not so distant future, but who knows.

Dosbox games (pre-1995 games basically) and ScummVM games (old point-and-click games) should be coming to Linux. Other than that you can Google the game to see which games have Linux versions. It's not 100% sure the Linux version will be on GOG but it's pretty likely.

...and The 7th Guest makes 5.

The Humble Store provides, if the developer/publisher so chooses, DRM free games and Linux clients, right now and has done so for years.

Also, what bugs me is that DRM free games with Linux clients like Limbo and Mark of the Ninja are not available on GOG.

I used to only use Linux (Slackware) at home and work as much as I could in Linux at work. Then I got a Window tech support job so I moved to Window at home to get myself re-acquainted with it. When GOG officially start supporting Linux again I'll probably get a second Hard Drive and install Slackware on it. I know it's not a supported distro but I'm confident in my Linux skills (once I regain them) to support myself. I've found that any other distros I've tried try too much to be Windows like and hide too much behind gui utilities that make hand modifying config files hazardous. Beside Slackware is the distro on which I found it easier to install software from source code.

I am now gambling on:

Penumbra Collection
Papers, Please
The 7th Guest
Expeditions: Conquistador
Amnesia - A Machine for Pigs
SteamWorld Dig
Sir, You Are Being Hunted
The Witcher 2

The above games all have existing Linux versions.

I've also done the prebuy on The Witcher 3, which is also confirmed as coming to Linux.

I'm hoping that these will all translate into DRM free Linux versions once GOG supports Linux.

I'm still waffling about gambling on The Last Federation and Rogue Legacy.

Another point you should consider is that if you buy these games now, they most certainly won't count as Linux sales, thus giving GOG more ammunition against Linux in the future. Some pretty unfair points against Linux have been made in the past by GOG which I won't name now, but do keep that in mind.

What if they count downloads as platform interest? So if you download the .exe it increases Windows platform interest, if you download the .dmg it increases Mac interest, and if you download the Linux one it increases Linux interest?
That would also help to properly judge interest of older buyers who already have a huge portion of GOG's catalogue.

Good idea, it would show, that I never downloaded any Mac executable here and every Linux file as soon as they are available.
At the moment for every indie game I consider buying I look up if it has a Linux version already and if it has, I don't buy it on GoG, so statement should be obvious if I buy them when Linux is supported here (if they were not available in some bundle in the meantime.)

If a business possesses that much common sense, then I'll be a happy lad. I have downloaded a few games for Windows, never for Mac OS, and I cannot wait to download whichever available games for Linux.