Dedicated user, iamlindoro, called and compiled a list of all the Apple Stores and whether or not they will be showing the WWDC Keynote in-store on Monday, June 23rd.
WWDC's Keynote will be broadcast to certain Apple Stores as well as by Satellite.
No official webcast has yet been announced.
The Full List of stores can be found in this thread. Please add your corrections/additions.
Keynote Time:
PDT/'Pacific' (UTC-7): 10:00 AM
MDT/'Mountain' (UTC-6): 11:00 AM
CDT/'Central' (UTC-5): 12:00 PM
EDT/'Eastern' (UTC-4): 1:00 PM
UTC: 5:00 PM