The official dates for the 2012 conference have not yet been announced, but a previously leaked guide suggested June 10th-15th as the likely dates. Moscone’s event calendar has those corresponding dates blocked off for a “Corporate Meeting” which typically acts as a placeholder for WWDC.
Insiders relays a report from GD that the new iTunes 11 is expected to launch at Apple’s Worldwide Developer’s Conference (WWDC) to be held in June 2012.

Event:
WWDC 2012 event = 11-15 June 2012

Products:
Mac OS X Mountain Lion
iWork 2012
iOS 6 beta 1 presentation!!!
iPhone 5 official resentation
iTunes 11 Presentation