I know what you're thinking. "Faggot." right? Well I'm going to explain the usual pattern you may have noticed with teenagers (girls are involved in this too, but most of the attention is focused on males) and young adults.
Now, most of us probably think this when they hear "My Little Pony".
Which is probably the gayest thing I've ever looked at, design wise. The art for the actual show was well color, but that's about it. The animation is awkward and the plot for the show is Godawful, not to mention that the writers clearly had no creativity. In the end Generations 1 through 3.5 (the picture being of gen 3) were just marketing ploys. If the kid liked the toy, they'd buy the movies, and if the movie looked pretty enough, they'd buy the toys.
Now, we get to Generation 4. I'm sure you've seen this little buggers everywhere, by now.
Obviously an entirely different style, the point one would think that Gen 3.5 and under were dollar store rip-offs. Clearly, it's colorful, but the art seems pretty doodly, more than anything. Then you may have realized that it almost looked familiar. All the concept art and such was done by Lauren Faust - most famous for being the creator of Foster's Home for Imaginary Friends (the last good Cartoon Network show), as well as having worked on The Powerpuff Girls and various other works.
In short, one of the more experienced (and one could say genius) cartoonists of our time, and while Hasbro still only views it as a marketing ploy, the creators of the show actually do a pretty damn good job with the plot, and even going as far as making references to the internet fanbase in their show (most notably the fan-named/personafied character Derpy Hooves, Star Wars, The Matrix, Chocolate Rain, Alice in Wonderland, etc.).
But Lauren Faust can't possibly be the cause of all this on her own, right? Right.
The pony's gained sudden popularity when a man on /b/ ranted about how much he hated the new shows that are being produced, and mentioned My Little Pony: Friendship is Magic by name. A few other /b/tards decided to check it out just to see how bad it was. They loved it, called OP a faggot, and spread the word.
The art was colorful and cute, the way all of Lauren Faust's works are, while remaining simple enough for the fans to actually draw it without having to take 2 years of art classes. The animation was smooth as can be (most of the time), while sometimes even surpassing the standard. The voice acting was actually pretty great, with each voice actor/actress getting pretty into character. Now, for me, what's most important is the plot.
The pilot episodes (if having a two-part episode as the pilot wasn't good enough) shows you both the background story of two goddesses who fought, one trying to take over the world, the other protecting it, and the evil one being sealed away. Twilight Sparkle, the (>implying) main character of the show discovered that this evil goddess would be freed one day - which happens to be pretty much tonight. FUUUUUUUUUUU-
So, after some character introductions, Twilight Sparkle assumes everyone in town is crazy and hates her life. The the evil goddess is freed and the good one is nowhere to be found. After some magical adventures and shit, they confront the evil goddess and prevail. In short, every Final Fantasy told in the span of 44 minutes.
Now, what's just as important (if not more important) to a show is consistency. I don't want Peter to try and help Meg become popular one episode, then the next episode hope she dies, Family Guy. The show keeps a very good consistency, making sure to never contradict itself, and (when it does) using reasonable patches and explanations and no bullshit excuses.
Now, with a less intellectual view on the show:
The characters are colorful, easy to connect to, it's a funny show, it's simple, and it actually likes the fact that it has fans our age. Also, it's great for inside jokes.
"We were making a table?"
Derpy Hooves:
Originally a background pony, who didn't even exist, other than her only line "Muffins!" and the time she accidentally dropped... I think it was an anvil? Well, her eyes crossed a lot, so she always had a DERP face, and the anvil thing implied she was clumsy, so the fans went wild with her (naming her Derpy Hooves, giving her a job as a mail pony, and various other things), and by the time season 2 was half way done, the creators of the show decided to make her canon, changing her technical name from Ditzy Doo to Derpy Hooves, giving her an awful DERP voice and persona, and, well... yeah.
A pretty okay personality test. The questions are randomly generated, so some of them might be a little odd. Or so I've heard. I only took it twice, but it seemed fine both times for me.
My result both times as extreme Pinkie Pie.