Generally using a camera which is hilariously tiny (phone camera, iPod camera, tablet camera, etc) would be a reasonably bad idea. Yes, it might have 5mp but that's just a selling point that Apple has, in order to go all "woohey look at this, its camera is tons better than the older one" when it still in fact is just a newer version of it. It might have 5mp but it's not going to be usable for serious stuff, other than taking pictures of flowers. The optic is tiny, the lens is tiny, think of it as a digital camera but just tiny. It's not going to work out, so if you're buying it solely on using it as both a, well an iPod but also as a camera for your stopmotion, then reconsider because it will not be worth it.
If you're buying it on grounds of solely using it as a camera for stopmotion, use the money on a smaller digital camera, a webcamera or, well considering it's Apple which means it's generally a bit overpriced, a smaller DSLR.
Just my two cents, I've tried the new 5'th generation camera and I'm telling you, it's a fine camera but it's nothing for what you want to use it for. I took this picture of a Mercedes I'll be buying next week, let me just find it
(click here for a 2048 x 1536)
That was taken with what is essentially a 5'th generation iPod camera. It might take beautiful pictures of flowers, cars, your cat but it won't be able to do macro stuff like doing it with minifigures.