Hi Bob:
Nothing is known at this time and nothing will be known until Microsoft makes it known. I think if I were in your position I would plan on Server because, and this is a biggie: If you are going to have Exchange you will need two servers
and Server gives you that for the cost of one license. Or at least it does now. As I just said, nothing is known until MS makes it known. <g>.
Larry Struckmeyer[MVP] If your question is answered please mark the response as the answer so that others can benefit.