Web filtering has come to the UK, and as you might expect it's been implemented in ridiculous ways, but because it's coming in bit by bit and over the holiday season it's really hard to determine how much impact it is having, and how much is due to seasonal dips.
You can use this link to check whether your own site is blocked, and at what level: [urlchecker.o2.co.uk
I'm not sure whether it's accurate, because nearly every site I've checked is marked as blocked at the "parental control" level, and I'm not able to test that. And when I say every site, I mean news sites, blogs, political sites, you name it. Even Disney, at some levels.