I would say something about how oddly human the pose looks even though you seemed to try with all your might to keep the horselike joint system in place, but considering what the show itself's been doing lately, especially in Sleepless in Ponyville, this is still much better. I guess your addition of the more humanlike-looking belly helps that illusion along as well.
Also, ponies in stockings. The next evolution of ponies in socks? One can dream.
I'm always impressed with how far you can push ponies while still making them look like four-legged creatures with bones and actual bodies and all of that. The show has always had them doing human-like "wild takes" but it's fun to push them towards being a bit more morphic in a different context. I've also given her very human-like hips here, for obvious reasons. I'd personally be very disappointed if ponies didn't have belly buttons.. it mans my elaborate plan to sneak up on Twi and give her a raspberry is doomed to failure.
Naw, it's working out just fine. It really does. I'm just thinking exactly how to proceed. Far too many ideas... You know, I'll simply improvise.
I'll do the unexpected and, in fact, my usual and give what I tend to call feedback. I like what you've done with the walls' texture there, it sort of appears between planks and the inside of an actual tree. Bonus points for them nice ornaments carved into them. Also, nice curtain, you managed to make its folds appear quite realistic up above the cord that holds it. The readable titles of the book are a nice little touch. As for Twily herself, the somewhat shorter than usual tail does work nicely here, as does the mane. The best part is her expression, certainly looks fine and fits the line in the description. Love those eyes with the beautiful eyelashes and that open mouth. The way she tends to lower her ear at moments like that adds to her cuteness quite a bit. The colour of those stockings feels just a bit too close to her coat, but it still works thanks to the white edges. And as ever, adding clothes to ponies makes them considerably more saucy. An interesting phenomenon. ... What? It being sexy doesn't mean I can't enjoy it from an aesthetic standpoint and note all those details that you've put there, maker.