I have a vodafone bill phone and am eligible for an upgrade. Do I have to do my upgrade in a Vodafone shop or can I go to non-network specific mobile phone shop (can't think of any off hand)?
Carphone Warehouse definitely do it, as do all other vodafone retailers as far as I'm aware.
If you trade in your old phone, battery, charger and manual you should be able to get a EUR30 discount at Carphone Warehouse.