Depends on how you are going to integrate these two. With Lync, its simply a SIP trunk from the Pool to the CUCM server. Then setup your dial plan to dial between the two systems. If CUCM is doing call control and you are using Single Number Reach (Remote Destination Profiles), then its still a SIP trunk to a secondary number on the Lync client.
Lync will use LDAP no matter what. You first have to decide is if Lync will use Enterprise Voice. This will help you organize your dial plan, LDAP telephone fields, etc.
