I conducted a forum search and found the following link, however; nothing definitive was found regarding a possible release here.

http://www.gog.com/forum/general/broforce_release_next_week

Humble has it DRM Free and I would not mind charity getting something, however; I would rather get it here if possible.

I think it will appear on GOG, because Devolver Digital is the publisher. And DD likes GOG.

New Devolver Digital games on GOG follow a pattern. They are either released here day-one (Dropsy, Hatoful Boyfriend, Hotline Miami, Not a Hero) or they don't get released at all (Heavy Bullets, Serious Sam 3, Talos Principle).

As far as Broforce is concerned, last news about the game were heard more than two years ago, with the developers considering a release after being contacted by GOG, but being reluctant to release an "inferior experience".

I know, same as Talos Principle. I'm just saying that the pattern with new Devolver Digital games is that they either release here day-one or they don't get released here at all. I haven't seen a Devolver Digital game release here after its original release date (unless you count the older games like Serious Sam and Shadow Warrior Classic or Ronin which was released one day later).

Did DD release Shadow Warrior (2013) on a same day on both GOG and Steam?

September 26, 2013. Day 1 release on GOG. Probably Day 1 release on Steam as well.

Yes. It was also a pre-order here.

Thanks. Asked that question because I think the unreleased games have legal issues (for example Duke Nukem 3D Megaton Edition) or the developers are not interested to release their games on GOG. They don't allow DD to publish their games on GOG. Wrong? Or is it a more complicated case?

Not sure about the other developers, but Croteam said that they aren't particularly interested in releasing the rest of their games here, because they don't consider it particularly profitable.

Bad news for me. :(
Because I have SS:FE and SS:SE in my library. And I expected to see all Serious Sam games on GOG. I like SSs very much. Croteam ruined it. :/

Thank you all for the replies.

Has anyone played Broforce? If so, what is your opinion?

Not yet since I am also confused and waiting for a release on GOG. You can buy it DRM free for months now on humble.
I played Expendabros which is likely close to a long demo. And I really liked it. They're not taking themselves too serious, obviously, it is relatively fast and fun gameplay, nice old school graphics (reminds me a bit of what I saw in terms of NeoGeo back in the days), controls are fine, difficulty is okay and you kind of have unlimited lives.
It's supposed to run on Linux, too, so I really want that game. If it doesn't show up on GOG I'll probably have to purchase from the people directly or from the humble store.

You can buy it drm-free on humble, although, it is still the beta version. They didn't update it to the final version yet, and I don't know if they will.

Update:

Well, so I bought it on Humble. The Linux-Version crashes every five minutes - unless you read your logs and find out that the game opens a ridiculous number of files at the same time. For security reasons the defaults for the number of files allowed to be opened by a process at the same time is limited. You need to set the number higher, then it will work and this fixes 95% of crashes. (Though it's not the first game to suffer from that, but the one with a really high number)

# echo "131072" > /proc/sys/fs/file-max
for a temporary fix

check /etc/sysctl.conf and /etc/security/limits.conf for a permanent solution.

The game itself is fun, thogh some of the later level have some elements that suck (possible spoiler: A run-away scene). And saving is done somehow automatically in a weird manner imho.
The final(?) battle crashed sooner or later but without an error message that would give me a clue.

So in short: Yes, fun, but somewhat buggy. Needs polishing to be real fun.