"We have received word that Apple retail stores have received unidentified shipments, as well as new signage, slated to go up on Monday. The London Regent Street Apple Store has received a single box that is padlocked, and under orders to be put in a safe until Monday. "Just one box?" I asked. Yep, just one... at this particular store, anyway."
This report is very similar to one we posted a few days ago about Apple resellers in Australia who received a mystery box.