This seems to be a question I'm asked a lot by all my friends that aren't yet parents...and, here's my answer.
EVERYTHING. In an amazing, perfect, and wonderful way.
I got a card today that pretty much sums it up, here's what it says (my pictures added for effect):
Your Baby girl
Every tiny yawn
every sleepy blink
and sweet stretch....
a miracle.
Sometimes you just can't help but smile with wonder at how good God is.
And this...this is one of those times.
how perfect is that? I couldn't come near to describing my feelings any better.