For me, Fallout 4 hands down. Just because I have uncharacteristically been sucked in by the hype and I am a massive fan of the series. Has a fun blend of plenty of action/FPS and traditional RPG elements (assuming it isn't a huge step backwards from Fallout 3).
That being said, as someone else pointed out, pre-ordering can lead to a lot of frustration when a buggy game comes out and Bethesda games tend to be full of them (partly due to their game design principles rather than negligence with QC). IMHO pre-ordering also encourages a lot of publishers to spend 50%+ of their budget on hype and marketing and as a result don't want to risk trying anything new, which I think is detrimental to the entire games industry.
If I am going to be biased and point a finger (which I am), Activision/Call of Duty are really bad with this, I find the Call of Duty series a real let down in terms of innovation over imitation. It's all flashier graphics, fancy gimmicks and very little real change from sequel to sequel. Publishers in this category also tend to be a lot less concerned with customer satisfaction and support as they have already made a tidy profit from pre-orders before the game is even released. It also leads back round to them releasing buggy games, because why not if they know they are in the black from pre-orders before they have even released the game.
Sorry for the rant, I should also point out I am a hypocrite. I will often pre-order games from a studio I love or because the pre-order discount is too tempting and as a result I have been burned more than once. However I feel much better pre-ordering from a start up or indie studio as they are often living hand to mouth as far as funding goes and not spending half their budget on marketing.
I didn't know Dark Souls III had been announced, thanks for the info
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