Who: Google+ has 40 million members, many of which who are professional or amateur photographers who participate in things like #SilhouettesOnThursday and #MyTownTuesday every week. In total, 3.4 billion photos have been uploaded to Google+.
What: A site that searches Google+ for the weekly tags of every event, and compiles everything into a beautiful at-a-glance viewer for every event.
When: Until someone else does it first!
Where: It would live at its own site and attract Google+ users.
Why: Everyone loves looking at amazing photographs. Curating them into one place allows for a much more in-depth browse. Additionally, having all of the events in a centralized place will help people remember what they are, because it's difficult remembering every event for every day: today alone I've seen more than 20 events for Tuesdays.