Would be cool to see this one on gog. I always hear good things about it. I'd like to give it a try via download and DRM free.

I definitely support this. Though of course it's a game the GOG-team is aware of, and would grab as soon as they got the chance.
Unfortunately, EA owns the rights to Alpha Centauri, and they have not signed up for GOG yet. There are many theories as to why, but the bottom line is that until they decide to offer their games on this service, we're not going to see any of them here, no matter how much we want them.
I'm optimistic, though. I think EA will show up here eventually, and I think Alpha Centauri will be one of the first games we get when they do.

Why people is not using wishlist? It is easier than open a new thread. :P

Well, the wishlist - as it is now - is useless and full of crap.

The forum threads that are begging for games are also useless and full of crap.

*insert generic mamma joke*

One could say the same of threads about the color of the underwear worn by soldiers in Afghanistan, for instance... at least these request threads are game-related. Also, there are many request threads which do contain interesting posts.

Agreed.
And I think that moving all the stickies into the 'Welcome, Please Read' thread was a bad move.
I know how annoying is having a bunch of stickies cluttering the board's first page, but this way makes it harder for newcomers to find stuff.
Maybe a collapsable section to hide/show the stickies could work better.

My personal experience in running and moderating forums in the past is that most people ignore the 'welcome' and 'read me' threads. Assuming that they are just a generic welcome and reprint of a EULA or FAQ. The 'important' thread becomes the equivalent of click-wrap.
The previously sticky 'GOG game suggestion' was a better idea. As are other threads that have a more attention grabbing title.
It's not going to be solved with those types, people are still going to create these threads, but it helps to reduce them.
I also like suggestions that have recently come up from other community members, about splitting 'General Forum' into a 'Game Talk' and 'Random' section. It will clean up General a bit, but leave the ability to post threads some of us don't want o bother with.

Maybe in GOG 2.0?

One can only hope :)
BTW, what happened to Dr. Evil ? A world domination plot demanded his attention ?

He made enough billions. Besides, Pingu is a fucking badass.

if people post threads about specific old games then we can, you know, discuss those games in the thread. Without making posts about old games the general discussion forum is gonna be pretty barren... or filled with random crap.

There's nothing wrong with discussing old games. It's asking for old games to be added to GOG that's the problem.