They haven't switched over directly 1 for 1 to the pound so the change has simplified matters for UK customers a lot:
"As many of you guys have pointed out in the comments section, Steam now also has a European pricing feature in BETA at the moment which, after the recent exchange rate shenanigans, stops Steam being a total rip off in the UK. To enable it, just click on the red text that reads: 'enable european currency beta' in the top right of the Store in your Steam client. You'll then be able to pick up Fallout 3 for the sensible price of £26.99, rather than the $49.99 (£32.69), along with a boatload of other bargains. Not only that, but the European prices even include VAT, so you won't get stung for extra cash during the checkout process either."
Also as that article points out they're only just introducing this in a beta form so I wouldn't get excited about it being some massive strategic blunder as it's clearly open for a lot of tinkering.
Also on a side topic the web functionality of the steam overlay is quite cool, does impulse do anything like that I've never used it?