So after many years of development, on August 17 2021 Joomla 4 has finally been made available.
More details are available at the Joomla website which you can find here.
For those of you that already have Joomla 3.x websites, be warned that although it appears to be a one click upgrade process; it most definitely is not! A number of the extensions that you might use are likely not to be compatible just yet, so take some time to consider your upgrade process.
Indeed I decided to start from scratch with this site, but using some SQL skills I have ported all my previous articles across, (for what it's actually worth!). In time I'm sure that someone will write an extension to make the process far simpler.