The other retailers that stock these have yet to follow suit. Google shopper reveals the next closest price is about £437. The question that remains though is “shall I get one of these” or “shall I wait for the new shiny tablets being released in a few months”.
Edit- As the day has gone on various other retailers are now selling it at this rate. You can now choose from Pc World, Currys, Dixons or Tesco.
The other thing worth noting is that if you buy one of these before the end of February you will be eligible for the Samsung entertainment pack. Which includes various films, games, books and music. In total about £200 worth of extras.