Okay, maybe its me, but I think BlackBerry knows that Windows 7 Mobile is coming and with Windows 7 Mobile, you do not need anything in between Exchange and a Windows Mobile device. So what does BlackBerry do? They release BES Express!
BES Express can be installed right on your exchange server or Small Business Server. With support up to 75 devices and near BlackBerry Enterprise Server capabilities, the price tag seems quite desirable. What does it cost you ask? Well apparently its free! Yes you hear me correctly free.
BlackBerry® Enterprise Server Express enables businesses of any size to quickly and easily get started with the BlackBerry solution. It provides advanced BlackBerry smartphone features with no additional software or user license fees, and works with any Internet-enabled BlackBerry data plan or a BlackBerry enterprise data plan.
For full details, and to sign up for notice of when the software is available, go here.