Usually we have a Pharo release each year in May - but the Pharo 7 release is now defered to the end of the year for good reasons.
The switch to git took a lot of time and is still ongoing with a rework in progress for Iceberg tool to simplify the UI. Also the 64 virtual machine for Windows and other important tasks keep Esteban busy. Additionally new additions to the Pharo ecosystem like the new Calypso system browser need to be integrated.
Which gives more time for contributions and cleanups. Meanwhile there are nice changes merge already (like the Shift class builder, latest Iceberg, many cleanups, ...) there are also nice additions in the pipe like the possibility to extend the Playground similar to Inspector or the possibility to use the foreign function interface without the source file in a deployment scenario.
Here is a description for the new contribution process. As an alternative you can also use my contribution project with scripts and a help topic to get you started easily. You can also use the new Pharo Launcher 1.1. or Fari - a shell to fetch and prepare new images. There will also be a Google summer of code (GSOC) in 2018 for the 14th year.
There are also additional sprint dates already announced till June 2018.
Jump in - the water is fine!