I just noticed this also, and It looks uglier than before, When did they change their interface? And why they changed it, someone knows? The very first page of blockchain.info doesn't seem to be runtime anymore(for the blocks) here in my mobile browser but it works on their old interface before, you have to refresh the page first before you can see if there's a changed. Don't like it.
I check the site on a regular basis and I noticed it hours ago , I'm not sure why they changed it as they didn't announce anything about it but I will assume It's because of the phishing attempts increase these days , changing the design and the icon as well (even on social media) could allow people to make the difference for the moment.