In reply to a post by Ragnarok:

donno but, most of the sites listed above that appear to be down on a BT connection I don't get a DNS resolution.

So it's hard to ping them to see if they are really down or just inaccessible via BT.

I'm pretty sure it's not DNS. I have a VPN that I connect to using just an IP address, and this is also coming up server not available.

I think it's nationwide (or, at the very least, all over the south of England).
I'm in Oxfordshire and have exactly the same problem...
... Loads of websites don't work at all - ebay.co.uk, amazon.co.uk, ukvac.com (an arcade machine forum).

BT.com works but is stupidly slow (probably getting hammered by thousands of BT Internet customers trying to find out what's going on)

Having trouble here accessing sites like twitter/ebay and many others.

Earl shilton exchange. HH5 reset hasnt helped. Can not get onto BT status page

downforeveryoneorjustme.com is down - or is it just me?

Same problems over here in N Ireland. Must be pretty much nationwide.

It seems that most UK sites are loading ok but all US sites are not working - I am using Google DNS. Unfortunately my HMA VPN is US based and I don't know the settings as their software can't connect to their server.

What's down?

No - I have just tried tethering via my Vodafone 4G phone and can get all the websites.

So it is a BT problem. A big one!

Have reported on the BT Care site - managed to get on using Google DNS.. Looks to be bigger than BT - if you can get to it http://www.internettrafficreport.com/europe.htm showing a few probs.. Torshavn routes a lot of US traffic and Cloudflare are reporting issues at the Frankfurt IX.... Only suggestion I have is enjoy the Tennis/Football today as I've a feeling this may be a while!

Same issues here in Newcastle (Benton exchange).

Can't access anything, except this site!