Back in February of last year, Google unveiled Accelerated Mobile Pages - or AMP, for short. In a nutshell, sites can choose to generate AMP versions of their pages (with an automated tool or site plugin), which load extremely quick compared to normal sites. This is due to various restrictions, compression on the included images/video, and caching by Google's own servers.
AMP support was initially only limited to mobile Google search results, but it has since been added to the Google+ app and others. Now AMP links have arrived in the Google Feed (previously known as Google Now). Just like with search results, a small lighting bolt badge indicates that there is an AMP version available.
While AMP links load extremely quick, all the usual complaints about them are valid here. It isn't immediately obvious how to open the normal page. Search results have a link button that displays the full URL of the webpage, but here you have to tap the overflow menu and select 'Copy link.' There is also no option to disable AMP pages entirely, which is definitely annoying.
I only noticed this change today, but Google has likely been testing it for a while with a limited set of users. While I do like how quickly AMP pages load, the implementation across Google's products often leads to confusion.