How do you tell them apart?

So I get this question A LOT. I usually answer "One is much bigger" or "One has a small skin tag" (that her vain mother is going to make sure is gone before she is old enough to realize it...it sorta reminds me of that dude in Shallow Hal). But what I really want to say is "How do you tell your kids apart?" I mean I know they are just curious, but come on! Charlotte has a shorter attention span. She is very demanding and cries to get me to pick her up when she is "done" with something. Dylan likes the mobiles more...she is much more content just to hang out and watch. Charlotte has much wider eyes, Dylan's are more almond. Charlotte talks more, her smile is big, wide. Dylan's smile shows no mouth, her lips just curl up at the corners.

Ok, so they both love light. They both are hell to get to sleep at night. They both make lots of grunting noises when eating and doing other things. They both love the stroller but hate getting into the car seats. They both are mesmerized by the tv (No, I don't have it on much but sometimes it is on while feeding them and they finish eating and their eyes go right to it. Scary).

But really, do you think as their mother I don't see them as totally different already?! As if!