Only if its from a developer I trust

Reviews, no. But I definitely watch dev videos/gameplay videos.

I'll look at reviews to watch gameplay without ruining storyline and such, but if I followed reviews, most of my library would be highly rated games, a lot of them that I think are overrated(from experience playing these games,) and the good games that I do like I might not even own.

Here's a list of games that I think are good but scored below 80 on metacritic. Yakuza 3, Yakuza 4, Mirror's Edge, Dead Space 3, White Knight Chronicles 2, Dante's Inferno, Twisted Metal, The Saboteur, Armored Core 4, Armored Core For Answer, Sports Champions 1 and 2, Army of Two the 40th Day, Dragon's Dogma, Lords of Shadow Mirror of Fate, etc.  I'd probably give some of these games a 7/10 but that's because my average is 5.5/10.

Reviews may convince to get a game I wasn't planning on buying, but they never dissuade me from getting something I want.

Dragon's Dogma is below 80%!?  But I loved it so much I bought it TWICE!!

*has heart attack*

*dies*

I do not read reviews but I check trailers and gameplays from youtube and such instead. If I like what I see I will purchase the game.

I only preorder for games with bonuses (which I rarely care for), or for games which may be harder to find after launch day (which I rarely feel to be the case).

I usually check out a few reviews to case out the game for bugs and major disappointments. Watching gameplay footage is more important in aiding my decision on whether or not to buy the game. For the rare cases where I can't get a feel for the game based on gameplay footage, I'll find a way to try it out beforehand or just make the plunge.

That said, many of Nintendo's core franchises are trustworthy enough to warrant a blind purchase, I haven't been let down by one yet, but I had seen reviews and gameplay simply from being interested in development of the game.

Same here. Most notably, I recently purchased Sonic Unleashed and Binary Domain - all based on people's feedback and footage.

Also, if I looked at reviews prior to buying any Neptunia game, I wouldn't have any of them

Some franchises and devs I will...but many times, whenever I have done so with other companies it has bitten me in the ass.

Never. I love reading reviews. Except if its a game from one of my favorite series then I'll likely buy it regardless.