Following a 'Limited Beta' phase, which began in September, the Let's Encrypt team has decided to roll out the service to the general public as a 'Public Beta'. "We're happy to announce that Let's Encrypt has entered Public Beta.", reads the Let's Encrypt's announcement, "Invitations are no longer needed in order to get free certificates from Let's Encrypt." During the 'Limited Beta' 26,000 certificates were issued.
In addition to the launch of the Public Beta, Let's Encrypt also enlisted Facebook as its latest Gold sponsor. Alex Stamos, Chief Security Officer at Facebook, statedd:
Making it easier for websites to deploy HTTPS encryption is an important step in improving the security of the whole internet, and Facebook is proud to support this effort.
Let's Encrypt is the brain-child of the Internet Security Research Group (ISRG) which comprises of many well known entities including: Mozilla, EFF, Cisco, Akamai and CoreOS, amongst others.
The main aim of Let's Encrypt is to offer an easy method for site owners to enable HTTPS on their websites. Before Let's Encrypt existed, getting a security certificate to enable HTTPS required a lengthy process of interaction with a certificate authority (CA), mainly for identification purposes. Let's Encrypt, however, doesn't focus on establishing a site's identity, rather, its aim is to switch as many sites over to HTTPS as possible so that users can connect over a secure connection.
Source: Let's Encrypt