Wireless sync is configured via the Zune software.

1. Have your phone join the wireless
2. While plugged into the PC, navigate to: Zune | Settings | Phone | Wireless Sync
3. Select your current home (or office) wireless network, and "Enable Wireless Sync"
4. The rules are:
• When charging and idling for longer than 10 minutes
• Within the selected wireless network(s)
• The phone will automatically sync photos, podcasts
• (email/contacts/calendar are synchronized with the cloud so those can happen any time)