Bethesda game studios (elder scrolls + fallout)
Monolith soft (Xeno series)
Bioware for the most part... they kinda dropped the ball with Dragon age for me, but otherwise their games are must-have's.
I would like to say atlus, but its just the persona series.

Falcom i love aswell. Every game they make is fun.

And finally, i F loved old SEGA. Best development house ever until it got gutted.

I love Sony in ways that maybe its illegal in some countries :P
and I love Guerrilla, all its games have been a treasure for me...

I focking love Square Enix, especially when in combination with Sony as a whole and Nintendo handhelds.

    Which Dragon Age did they drop the ball on? Just curious.                         

Please credit where the credit is due. Bungie and 343i. I am going to assume that you Bungie is the big favorite here. Bungie is an incredibly talented studio. Some of the best of the best came from them. Another outstanding title the've made is Oni.

I like the GGG shoutout. I agree, a f2p version thats a million times better than Diablo III, how can you not love those guys?

mine:

I f***ing love Square Enix.
I f***ing love Atlus.

Gameing is a better place thanks to these guys, Love their RPGs.

2 and Inquisition. 

I fucking love from software since demon soul's.

Running With Scissors, because they just don't give a shit.

SCS Software, because I'm seriously addicted to Euro Truck Simulator 2.

Metro Corporation (aka Metro Graphics), because they made that one Britney Spears game all the way back in 2002. Even though it sucked hard, I don't care. =D

I fucking love Atlus.

I mean, it's Atlus. Unless you hate RPGs, I don't see any reason to hate these guys. They're amazing.

I fucking love Monoltihsoft. Complete fanboy of them and have loved a lot of their creative staff's works for as long as I can remember. Tetsuya Takahashi is an absolute genius of the genre, bar none. Literally no one can touch that man when it comes to storytelling.