We run our company email through an Exchange server. We access our email on our desktop PC's through Outlook 2007.
We are able to access the Exchange email, contacts and calendar entries on our iPad 2s.
All of this works great, however if I make a change to a contact in Outlook, it doesn't update the contact on the iPad 2.
Yet if I add a new contact to Outlook, it will sync it to the iPad just fine.