We've been taking weekly pictures of Carys since she was a week old. The theory sounded better in my head, before I thought about the fact that doing so meant that we'd have to do this at least 52 times. Montly pictures are the way to go, I think. But now we're commited, so I'll give it the old college try. Meaning, I think, that you get drunk and sleep around.
She's only two inches longer now than she was at birth (well, 2 and 3/4) and weighs two pounds more. It's hard to see how much bigger she actually is in these pictures, except in the one month picture where she somehow looks gigantic.