Well since I can't do a second vote I'll just vocally say probably G&G 0.5 although I have not played T2K or the DHW set. But there are so many things that mod does I love. The soundtrack is great, even if none of it is original (although those boss levels use remixes of Doom (II) tracks that I have not heard before). I'm with ronwolf on the projectile based shooting. It makes the whole game feel like something unique from everything else. A few people won't go so well with the change, but in this case I'm not one of them. Then you have good use of textures, shading, etc. along with good mapping, i.e. all the basic requirements of any good mod. Sure T2K and the DHW set are almost shoe-in to meet every requirement of a great Wolfenstein release, but they aren't going have features that allow a step far beyond it like GG and Eisenfaust do.That is how you get release of the year.
My only question about Guns & Glory 0.5 is: Why is it 0.5? Is it like only half-finished or something? I know there's the community set that may come for it, but nowhere do I see that the story itself is going to be expanded. It's also the second mod with the main name Guns & Glory. Little Cherub's release in 2007 (which, while completely independent of this 2012 GG, I also enjoyed a lot) is the other one, called simply Guns & Glory with no additional words in the name. Did Metalor want to call it 0.5 because he thought it could not possibly be as good as Little Cherub's release (and I don't think that's even true) and thus the 0.5 is simply meant as an admission of inferiority/incompleteness compared to the 2007 release (even if it isn't actually inferior, at least in the opinions of many in the community)? Or is there some other story behind things? As far as I know, the two don't share any of the same levels.
But it's not relevant to voting anyways, because I don't judge something by its name.