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From the Apple Switcher site:

"...export PC contacts to vCards, and import them into your Mac Address Book"
 
http://office.microsoft.com/en-us/marketplace/EM102141191033.aspx

But, Outlook only lets you do this one at a time...one option is above.

Outlook® to vCard, vCalendar or iCal converter

Microsoft® Office Outlook® allows you to convert only one contact into a vCard formatted file at a time. With 4Team Corporation’s vSync add-on for Outlook®, you can convert any or all contacts to the vCard format. Convert all or selected Outlook® calendar events into the vCalendar, iCalendar, iCal format. Filter contacts and calendar events during import and export. Export contacts or calendar events into one file compatible with Lotus Notes, Google Calendar, iPod, and Mac.
 
Export your contacts folder to csv from outlook. You can import that file into address book

Outlook 2003 Wont let me do that format. and my Work server seems to be blocking my mailing of the vcards. I HATE WINDOWS
 
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