Not really... I made marginally more in the US than UK but it wasn't a great deal. That said, I had a good gig in the UK. Worst case, it's not order-of-magnitude different, and besides: proximity to Europe and a culture of realistic holidaying makes up for it (and ... cheeky as it may be to say it ... co-working with people from around the world wins hands down on being stuck in an office 355 days a year with Americans).