You can still reserve to pick up in store at a set time in the UK, you pay when you arrive. This is not the same as Local Pickup in the USA where you pay online and collect in store.
Just image Currys - reserve your TV, turn up with a reservation number and your TV is waiting. If you don't turn up that day, its available for some one else to buy.
Ah, OK, thanks. If that's true (like how the handled the 6/6+ reservations), then that's great. I presume you'd even be able to try it on then before purchasing?