Former AT&T Wireless Site Leases

I'm curious. What will happen to the leases for AT&T (or Cingular) Wireless sites where there is a close overlap between the two? For instance, near my house, there is a Cingular Wireless site mounted on a old, unused smokestack, and across the street is a similar site that is a AT&T Wireless Site. I am sure once the merger is complete, they will want to eliminate one of the two sites, and