Product Management tends to be about answering questions such as why a product should be built and what features should be added to existing products. Program Management is more about answering questions such as when features should be delivered and how they should be exposed to customers. Depending on the division at Microsoft program managers may have more or less influence than product managers on answering the questions about what features are built.
Developers tend to spectacularly underestimate the effort involved in such a rewrite (more on that below), and spectacularly overestimate the value generated (more on that below, as well).
One day, I’ll grow up enough to use an organization tool. This one will probably be it.