actually, i think they have designed a way to keep kittens as kittens. but im not so sure, just something i heard from some dude. But that dude is usually full of shit.
My other cat Loki is kinda fat like the one you posted Shadows, he's two and still awesome. I think overnight he must have put on like 10 kilos cos he seems sooo much heavier now that I've got a kitten that doesn't even weigh 1 kilo..
Some more pix:
For those who haven't seen Loki, here he is in all his glory: