Guh, every time, every bloody time Apple launch a new product someone cocks this calculation up and bitches about it. US prices do NOT include sales tax, UK's do. Using the base macbook as an example:
UK Price - £999.99
UK Price without VAT - £851.06
UK price in Dollars at current exchange rate of 0.6483 - $1,312.74
US Price - $1,199.00
Difference - $113.74
That difference has to cover any additional taxes that get paid to the UK government, higher transport cost, additional costs from lower volume of devices (UK localisation costs) and also absorb any short term changes in the interest rate. It's actually pretty damn close to where it should be when everything's taken into account so if you want to blame anyone blame our lovely money-grubbing government.