I tried to visit the EL&U blog and I get redirected to the Stack Exchange blogs main page.
If I try to visit one of the EL&U posts that are listed on that page then I get 404'd
Where has the blog gone?
It wasn't just ELU, but has now been fixed:
This was an issue with the SOA and A records being cached really hard on some DNS servers for a day. We never had a TTL higher than 5 minutes on the A and no higher than an hour on the SOA at any point, so we're at a loss to explain why some downstream DNS servers chose to cache for a full day.
The records in question are fixed now, but if you had this issue then beware your DNS server. It, or an upstream server, is not configured properly.