So I noticed five games updated on Galaxy for my library recently yet no updates have yet to post in my library. Slain being one of them has had an update out for some time now, yet nothing in the library downloads for me. How long does it actually take for the library to update? Seems it is taking longer than usual.

It could take a few hours to a few days from the impression I got from past discussions. The way in which updates are prepared for Galaxy distribution is entirely different from how they're packaged up into the installers (which takes more work), so there can be some time delay between when each become available. This is normally not noticeable for older games and games that aren't updated frequently, but newer games that receive more frequent updates could potentially experience a bit more lag time between the two from what I understand.

Galaxy is still showing as BETA release on https://www.gog.com/galaxy ,
so I guess it could take 24 hrs or more for Galaxy DB to sync up.

I will be genuinely surprised to ever see it move beyond that.

Actually the time of a patch arriving on gog after it has been sent in by a dev is usually within 24 hours if it's a working patch. However it can take up longer if it's done on a friday after gog closing hours. But generally it arrives within 24 hours. Unless the patch breaks more stuff than it adds. Or the game gets patched very heavily and a patch is not noteworthy in which case the dev sometimes waits before sending a new patch to GOG. This is because GOG does quality assurance as well to make sure the patch does what it intends to do.

I figure Galaxy will move beyond beta status when/If the Mac & Linux Galaxy clients get released.

There's already a beta version of Galaxy for OS X; it's just the Linuxers who're waiting on a native version.

Remember how Gmail stayed in beta *forever*? And yet it's out of beta now...

Yeah, but Google didn't have GOG's "top men" working on it :D

Maybe Galaxy will come out of beta when CD Projekt releases Cyberpunk 2077.
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.......oh wait, there hasnt been any cyberpunk 2077 news in 3 years.

Well, what do you want? They've got 60 more years until release!

I think I remember reading something to the effect that there won't be much news coming out about it until 2017.

61 years, technically.
Or maybe it will be renamed Cyberpunk 2038...in honor of that sort of millenium bug 2.0
https://en.wikipedia.org/wiki/Year_2038_problem

[throws can of soup]
[clambers up on stage, retrieves thrown can] I'm terribly sorry, I didn't mean to throw that. My sincerest apologies.
[climbs back down from stage]
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[throws tomato]