As a side note, I see that everyone I've looked at charges somewhere around £6-£7 for a .co.uk, but .com are split between companies charging around £7-£8 and ones charging £12-£15.
Any idea why the difference? Surely there's a registrar cost (same for all providers) and then their own costs on top (same for all types of domain within that provider). But that's obviously not the case.