Baby will be laughing and giggling a lot this month, and will coo and gurgle even more. His personality will be coming through, and his methods of vocal communicaion are becoming a little more varied. The best thing you can do is play with him and encourage this communication and development even further.
He will also be staying awake for longer periods of time now, and sleeping in a much less broken pattern. This really is when you should start getting much better quality sleep overall. His motor skills are also improving, with much waving of arms, kicking of arms, and batting toys with a closed fist.