It's really sweet that it's a GIF's but not really an 'animated GIF'. Just an illustration with a few slighty moving bits to make it feel alive a little more.
Noticed the steam from the cup right away, and thought it was a really neat little thing you added. Then I wished you'd put in some more little moving parts: then I noticed the blinking eyes in the window-reflection, nice.
Then I thought it should have some more things to make it complete, like making the water move/reflect the light a little, or should have some stars twinkle. Then started looking a little closer in the sky and saw you made the big star twinkle ever-so-slightly. That made it the cherry on the cake.
Have to say that I probably wouldn't have batted an eye on this, if it didn't have the moving parts (or didn't hit the frontpage): the line art looks rather simple, well-done though, don't get me wrong, but nothing that really grabs your attention right of the batt.
The animated parts just added a really nice and comfortable viewing tempo (if you know what I mean). It's like you don't have to look at the whole thing right away , to take it all in at once. But you first look at the steam: your eyes move to the right cuz you see the blinking, then move to the upper left corner, and look at the other details allong the way.
Simply put, it worked with the composition to make the viewer take a path to look over the whole thing. So it helps out, to have people look at everything put into it.
Would be cool to see, if you could take that concept a big leap further: like also putting in more little moving stuff in the surroundings, like having the water move or have the trees move a bit by the wind, or other little things you could think of. Though it would probably be tricky to time it all and have it all look seperatly moving in one GIF. And having it loop correctly.
Anyways, nice job! ';D