A. Exchange 2007 does not have its own routing topology. Instead, it relies on Active Directory (AD) sites and associated site link costs. If there are situations where the AD site link cost does not meet your requirements, you can set an Exchange 2007-specific site link cost using the following command:
Set-AdSiteLink -Identifty <AD site link name> -ExchangeCost <value, e.g. 50>
In the future, I think Microsoft will use this procedure to link everything together, including automatic information gathering. In 10 years, I suspect these tools will dynamically assess the environment, client usage, and connectivity, and then dynamically create additional virtual servers to meet demand in the most efficient manner. Time to learn how to be a plumber!