Facebook announced Instant Games for Messenger in November of last year, and since then these have been available to users of the app located in the US. From today on, however, Instant Games will be rolling out globally to Messenger's 1.2 billion users (and the rollout will take a few weeks to complete, Facebook says).
Additionally, rich gameplay features (such as turn-based games) are built into the experience now, as well as game bots - which help game makers call out stuff like new levels and rewards.
The selection of games has been expanded too. Depending on where you are and what device you're using, you can access up to 50 titles, with more coming every week. Words with Friends is on the platform, as is EverWing, and 8 Ball Pool is coming soon. EverWing is among the first to use game bots, and Words with Friends takes advantage of the newly introduced turn-based gaming abilities of the platform.