This is one of my favourite illustrations of yours, definitely! I can't stop looking at it, it's fantastic!
The light-hearted atmosphere can't help but make me happy, too, it's so nice to see that side of them once in a while..(okay, maybe more than once in a while). And oh, man, the details... Every single one of them is PERFECT! Their clothing, the expressions, the gestures... Hedwig and Pig and Crookshanks, the background (especially the window's glasses - do I see a Snape there?)... Just EVERYTHING! I love this to bits!
Teehee, is that poor owl crashed into the window? Reminds me of the scene from "Up"... Hermione actually makes me laugh a lot ("I imagine 'nothing''s in the back getting more mead")- or something along those lines. Lovely, per usual!