You can still get the World Service in the UK on DAB digital audio and via the internet - if you go to the world page on the BBC News website, there's a listen live button for the World Service on the right towards the top. But 648, which has served the south-east of England, and parts of the continent, so well for decades is dead - a victim of public spending cuts.
I have a very nifty old portable radio in my bathroom wonderfully aligned so that if I press the FM button I get Radio 4, and press the MW button, it's the World Service - with no further fiddling required. Today the MW button produced just static mush. I tried in the car where 648 is pre set - the steady hum of nothing in particular.
So I've bought myself another digital radio - they're not exactly cheap: one in the kitchen, a portsable for my jacket pocket, and I guess I'll have to get one of those plug-ins that should work in the car. So sorry to see you go, 648.