Time for a little bit of critiquing, and since you asked for it, I'm ready to supply it! Let's get right to it, then!
Your vision seems to be realized just fine. You wanted to do a picture of Apple Bloom and Granny Smith loop-de-hooping, so you did! It gets the point across, and there's not much more to it than that. It's a fairly simple concept with decent execution, and I think you pulled it off.
The originality of the picture is pretty high, too. Although a similar pose was used in the show, you used different looking versions of the characters. While Apple Bloom doesn't look too different (And she shouldn't, really), it's different enough to make it unique. So, you get pretty high points for this category.
With this piece, I feel that the technique is the weakest point. Now, don't take that the wrong way! It looks good overall, but you could have done some things differently to make it shine. For example, the lines are a bit jagged at points, and not all of the same thickness. By getting them smoother and conformed to a size (depending on where they are, of course), this would look a lot better. Another thing to note is that the hoop itself seems rather flat. It needs outlines or some sort of definition on it. I commend you on the tapering you've done with the lines, however.
Finally, the impact of this piece. This category is a little tricky, because it depends on the artists intention. In this case, it was just a picture. It wasn't intended to probe deep thought or examine a theme - it was just meant to be a nice image. It does that just fine! It's a nice image and evokes a few thoughts such as "D'aww" and "Cute", so that's good. While not the most mind-blowing piece of artwork, it certainly meets the criteria for fanart.
Overall, the piece looks good - could be better with a few changes - but other than that, you've done some decent work with the drawing. Keep practicing and your future work will shine!