First off, Blackberries don't sync email. Email reconciliation and email sync are not the same thing (I haven't checked the FAQ's on this but there's likely something there on this). If you're looking for email sync you won't find it on any Blackberry, BES or not.
Originally Posted by salsa
BES does do all of the agove but the BES hosting service probably requires Outlook because they have most likely setup the BES with Exchange.
Some of them will assist with getting Entourage set up with Exchange but there are some limitations, IIRC.