Congratulations. I've got a 1 yr old but it's funny how quickly you forget all these things. I've just looked it up in my book & it says at six weeks when they start to smile that the baby will now recognise your features, ie eyes, nose & mouth, rather than just your outline. It will also enjoy watching things at this age so will be interested in a cot mobile or bright colours.
If you are interested, the book I have, which I found really useful, is 'Your baby week by week' by Simone Cave & Caroline Fertleman. It's so exciting reading what your baby will be doing each week, and I found it really accurate.