This is by no means an exhaustive list (it's just a fraction), that's what the comments are for to tell us what you're looking forward to if we didn't include it, and to tell us how horrible we are for not putting it in.
7 Days To Die
Age Of Wonders III
Borderlands 2
Borderlands: The Pre-sequel
Civilization: Beyond Earth
Chivalry: Medieval Warfare
Clockwork Empires - First build for Linux is due next month.
Company of Heroes 2
Counter Strike Global Offensive - Showing more signs of it being this year due to their recent blog post!
Darksiders
Darksiders 2 - We don't have word that it will be this year, but it's possible.
Dead Island
Empire: Total War
Football Manager 2015
Half Life 3/troll
Killing Floor 2 - Not confirmed, but hopeful for this year
Metro 2033 Redux
Metro: Last Light Redux
Outlast - Probably one of the scariest games ever made, but it's not confirmed it will be this year yet, but it's likely.
Risk Of Rain - On the 30th July they said it was coming along well.
Shadowrun: Dragonfall - Director's Cut - 18th September
Super Win The Game
Stronghold 3 Gold - If you can put up with the crappy pathfinding & AI.
Terraria - Just recently confirmed officially as in-development for Linux/Mac.
The Binding of Isaac: Rebirth
Transistor
Tropico 5 - 19th September!
War Thunder
Wasteland 2 - 19th September!
That's one hell of a list not counting plenty of others. My wallet has sprouted legs and is off cowering in a dark corner right now. I feel so terribly sorry for my wallet.
Could this be the best year ever for Linux gaming? Stupid question, of course it is!

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