Looks like the development kit for Windows Mobile 6 is a nice one - it appears to be robust enough that most folks won't actually need to purchase the devices they're writing apps for. This page has a few more details - most of which are mysterious and arcane to a non-developer like myself. Of course, some of you may have already grabbed it when it was accidentally released early in February.

The Windows MobileĀ® 6 developer platform release focuses on a few core goals: simplify line of business (LOB) application development and deployment, make the task of building a single application that runs successfully across the many different devices in the Windows Mobile family easier, and provide an enhanced user experience

Read: What's New for Developers in Windows Mobile 6