Around 600 Mac fans queued up on London's Regent Street on Friday ahead of the 6pm release of Mac OS X 10.5 Leopard.
Apple had closed its shop in advance of the 6pm deadline, causing excited customers to queue outside. Apple staff, meanwhile, busied themselves installing the new system on the store's demo Macs.
North of the border in Apple's only Scottish store, on Glasgow's Buchanan Street, queues of Mac users were also seen waiting for their chance to buy the evolutionary new operating system.
Similar activity has been reported across the UK, as Apple resellers this week announced their plans to open late for Leopard.
Analysts have estimated the release will accrue $240m into Apple's coffers.