Looks like Research in Motion has recently released Pocket Mac for BlackBerry 4.0 which is a free BlackBerry download available on on the BlackBerry.com website.
According to macnn.com, Pocket Mac for BlackBerry 4.0 “can sync entire Entourage Calendars, Contacts, Tasks, and emails as well as Apple’s iCal, Address Book, and Mail Apps. PocketMac 4.0 also syncs DayLite, Meeting Maker, and more.”
I’ve been using v4 with the new Blackberry Pearl (8100) and it works quite well. A quirk is that the 8100 reports an under-current condition for charging when plugged in, but it charges fine anyway.
What DOESN’T work is file transfer via the “Browse Device for Folders and Files” option in the Utilities menu. This option is greyed out at all times and Blackberry confirms that it is a forthcoming feature (though its presence in the menu would seem to indicate a bug rather than a missing feature). This coupled with the fact that Blackberry has broken the Bluetooth standard in restricting the transfer of files between Blackberry devices means that Mac users have no direct method of moving files back and forth to their devices.