The Blackberry Desktop manager allows you to configure the synchronization
process through the "intellisync" portal installed with the desktop manager.
From the "Synchronization configuration" select the synchronization button.
This launches the intellisync application; select the "address book" and then
select the "advanced" button. Intellisync provides an option to "filter" on
various internal outlook contact field names when any existing filter is
edited or new filter is created. Several posts on other sites suggest using
the "Categories" fileld to set up differences between Business, Personal or
"other" category for each contact. Once categories are assigned, you can use
the filter feature to synch up only the ones you need... I haven't
physically done this at this point, but have used the filter to only filter
contacts with phone numbers or email addresses and it worked fine...