Deathinitive Edition will include all DLCs and is supposed to be using a revamped engine but I couldn't spot any significant difference on screenshots. Only worth a shot if bugs and glitches were fixed.

For the Steam version Nordic decided to screw most people.

For the free Upgrade it is not enough to have all games, the Season Pass and all DLC, no - only owner of the Franchise Pack will get the free upgrade. So everyone who bought the franchise pack sometimes during a 75% sale is getting the upgrade free, everyone who bought all content at full price has to pay again. Great Nordic and the next publisher is on my blacklist...

Yeah, while I still enjoyed Darksiders 2 and think this is cool, the first game is far, far better in my opinion. Hopefully we'll see it get its own shiny upgrade in the future.

I don't really see the point on this upgrade they could have just upped the textures not mess with the lighting and remove effects and add a lot of bloom, eh whatever but I hope they could do the 3rd game with the other character that was suppose to be done :(

They didn't want to do things that way for Steam, but they were told that their original plan wasn't technically possible:

"Our original plan was to have the free copy unlocked for everyone owning Darksiders II and ALL DLCs but unfortunately this was technically not possible so we were told and therefore we chose the Steam version being the one unit unlocking the free copy which is as close as possible to the content we wanted our loyal fans to own - the Darksiders Franchise pack."

I'm still hoping for the previously mentioned Linux version of both games.

Please?

It is possible.
Deus Ex: Human Revolution DC Upgrade Deal:
http://eu.square-enix.com/en/blog/dxhr-%E2%80%93-director%E2%80%99s-cut-pc-digital-release-details
2013 it was possible to differ between owner of the base game and owner of game+DLC.

http://www.polygon.com/2015/3/27/8300373/dark-souls-2-scholar-sin-pc-steam-upgrade-price-directx11
Still possible in 2015 to differ between people who bought the only base game and people who own all DLC, too.

So it is possible to offer a free upgrade to everyone who own the base games and the season pass or Season pass content - they decided against it. Two options, they don't know who to use Steam or they are lying.

You are wasting your time trying to talk logic to steambrains and steamfans. They cannot comprehend the simplest of things. Besides, when WE nag for the exclusives and bonuses steam generally enjoys while we don't and that is unfair, they even attack us. In my book, serves them right, let them wear our shoes for once to see how it feels to be last, for a change. Maybe they can be changed into true, both-ways equality-seekers in the process, but i seriously doubt their potentiality and evolutionary abilities.

Some parts look better in the original pc version. O_o

Since the PC version of the Dethinitive Edition isn't out yet all graphics comparisons I've seen up to this point compare the standard PC edition to the console Dethinitive Edition. Keep in mind that the PC Dethinitive Edition will most likely look better than the console one.

Will getting your fix with wine helps?

That didn't happen for all people who bought Dark Souls 2. Those who bought in Japan didn't get the offer as it was a different app id.

If only I had the first Darksiders here instead of on Steam then I would have been eligible for Tier 1. When I bought Darksiders I had no clue the games would come to GOG as well. Anyway, good on Nordic for providing the Deathfinitive Edition free for owners of the Darksiders franchise.

So my GOG version will receive the update, but my Steam version won't?

Ok, fine by me. :) I prefer it this way than the other way around, how it usually goes.