You may choose to disbelieve this source, and I'm not going to spoiler tag it because you can pretty much figure out how this season finale is going to end by just watching the first episode. Corporate greed is once again destroying the pretty things.
I believe what is stated here because I had the same suspicions since before season 3, where "crystal ponies" (which are no mythological creature that I've ever heard of) were announced to appear for no reason in the show, but their toyline was already in stock for sale.
Yeah, I know some of you bronies are gonna go "I, for one, welcome our new alicorn master" but remember that Season 4 will most likely be one random, pointless episode after another, just because somebody wants to sell moar merchandise.
For those of you unfamiliar with what's going on, let me put it in a nutshell. There was once a company who made crappy toys and lame cartoons to advertise them (Like Transformers and My Little Pony G1-3). In 2010, they made the mistake of hiring actually talented people for another shot at this failed MLP show. They made cartoons that would actually educate your kids instead of brainwashing them. Meanwhile, Hasbro tried to make toys that didn't even resemble the characters in the show, like an imitation of Princess Celestia (an ancient God in the show) that says wise things like "My wings are pretty" when you push it's bottom. They either couldn't make better toys or didn't want to, but now they want to lower the level of the show to that of their toys.