Perfect Rotation!
Perfect Rotation!
Perfect Rotation!

Applejack, Rarity, and especially Pinkie Pie have made use of prehensile tails before. (Applejack instance being holding a rope with her tail rather than the below-mentioned instance of brushing Rainbow Dash’s face. This was in the sixth episode of the series too)
 
It’s a bigger deal for Fluttershy because it debunks the rumor of her using tail extensions. (before this episode she didn’t often make use of her tail unless she was Discorded or Flutterbat, but she DID pick up the Breezies with her tail if I remember correctly)
 
Of course any uses she has for her tail as her true self qualify as cute, because Fluttershy. :)

If you can dodge her cuteness, you can dodge a ball.

@Blissey1  

 
I was mentioning one of my finds.

@LeAlbinoPony  
Uhh… What does neopets have to do with mlp canon?

@Background Pony #19E5  

 
It wasn’t just in MLP…
 
 
Figure 1
 
 
Figure 2
 
 
Figure 3
 
Certain species of Neopets, – such as the Kacheek (Figure 1), Korbat (Figure 2, left side of the image), and Mynci (Figure 3, left side of the image) – have a prehensile tail as well.
 
(Image source, Figure 1-3: Neopets.com)

When she finally lets that fastball go, the catcher gon’ lose some teef.

@Background Pony #19E5  
So he got the wrong kind of tail use, we have seen prehensile tails as early as season 2 anyway.

@sumbozo  
Prehensile means grasp not whip.

OOOOOHHH AND FLUTTERSHY PULLS OUT THE NEW SIGNATURE MOVE—THE FERRET FERRIS WHEEL OF MISFORTUNE!!!!! SHE IS––UNSTOPPABLE!!!!!!

Skillz!

OH WE AY  
TALESPIN

@Background Pony #19E5  
They always have been.  

She then throws the ball with the speed of an oncoming missile and utterly wrecks whoever or whatever gets hit.

@Corrderio  
Aww, you beat me to it!

Ballspin

For some reason, this gif looks like it would go good with wubs. If it can be done with sweeping, it can be done with this.

spin to win

You spin me right round, baby  
Right round like a record, baby  
Right round round round

Prehensile tails are canon.