I think this comment thread proves there kind of was a rivalry lol.

I watched LPS first, And I prefer it. And I was a Pet-aphile/Petter (LPS Fan) before I was a brony. So, yeah.  
Just saying…..
 
Because of the description and multiple people in the comments.

@Niggoslav_Krawczyk  
Ha that was in the first episode. I wouldn’t mind seeing where they did an episode where Blythe got her ability to talk to animals.

Biskit twins are hilarious.

@Niggoslav_Krawczyk  
wut? 0.o

@Grieffon  
You probably should have, you missed the best reason to watch it right there! :D  
 
Meeeeoooooow, baby!  
Now if they did more of that and had less Blythe (anywhere, ever) then boom baby! Ratings off da charts!

@igotnopicks  
what?

Bronies and LPS fans are rivals? Well, I never heard of that.

@Background Pony  
And that too.

@igotnopicks  
They almost were with the conference realignment

@kristy  
Thank you

@kristy  
Who says ‘I is smart one.’ But yeah I understand it’s an analogy. But that doesn’t mean that the San Jose Sharks and the Winnipeg Jets aren’t rivals thanks to this guy.

@Itsthinking  
it’s the same voice actors

@igotnopicks  
nah, you are just trying to get out of looking stupid

I have nothing against The Littlest Petshop or their fans.  
This idiot is trying to start shit.

@kristy  
I wish he was. It’s be more interesting.

@igotnopicks  
ok, since I’m tired of seeing so many people not get the referance, he isn’t talking about the sports teams.  
http://en.wikipedia.org/wiki/West_Side_Story

@Grieffon  
I’ve seen a few episodes, they get better later in. “Topped with Buttercream” is one of my favorites, though it does really show the problem the show has with subplots. “Sweet (Truck) Ride” is good too.
 
Basically, they go to a sweet shop and meet a hyper rabbit with the voice of Spike and then meet a stoner cat with the voice of Spitfire who makes them like sprinkles off her body.

Nope, my arch enemy is Captain Hammer.

@Petedash  
Exactly. Don’t state your opinions as if they are facts.

@elactor  
Sharks being San Jose, and Jets being Winnepeg.
 
No they are not rivals.

What the shit is LPS?

@Grieffon  
It’s only opinions everywhere. Like your own comment.

@Petedash  
Again opinions. I enjoy every single episode of S3 except Games Ponies Play. And I didn’t bother to watch ep 2 of LPS.

@Niggoslav_Krawczyk  
A Friend in Deed, Applebuck Season, Green isn’t Your Color, and Putting Your Hoof Down all seem to have been lifted directly or in part by several episodes.
 
Sure the “Mean Isn’t Your Color” episode was written partially by FiM writers, but the others? Nope.