Steve Ballmer finally admitted yesterday what some had rumored in the past, that Microsoft was planning an Enterprise version of WM7 alongside a consumer version. It will roll out based on 6.5 to start and then transpose into WM7 later next year. Here’s Ballmer’s quote from PC Magazine’s report:

"Microsoft will soon release a new mobile OS for embedded and enterprise devices based on Windows Mobile 6.5, to be followed by an enterprise-focused version of Windows Phone 7 in 2011, Microsoft chief executive Steve Ballmer said by video at the launch of a new Motorola enterprise smartphone on Thursday."

The new phone is Motorola’s  ES-400 phone to be handled by Sprint’s Enterprise Division.

The ES400 runs on a 600-MHz ARM11 processor. It supports GSM HSPA, Sprint’s CDMA EVDO, and Wi-Fi 802.11 a/b/g – yes, that’s "a," which is the relatively unusual high-speed Wi-Fi variant used by some large businesses. There’s a fingerprint reader on the back. Every part of it is rugged, including the keyboard. Making the device rugged greatly prevents failure rates and saves companies $500 per device over three years, Motorola said.