Cute. :3 I think that it might look a little better if there was a flat surface underneath him. Then the squishiness would look perfect. I think it throws some people off because it appears that he is bouncing of of something flat when there is nothing there. :>
It certainly feels squashed and stretched there... so much that I fear for its life. o.O
I really like the fluid grace of it all, and I think it's quite awesome how it's so lively as well. I do feel that it wouldn't hurt to emphasise the circular structure, but...well, you're stretching it, so it's understandable that it loses its form a bit.