The waiting is over! QGIS 3.0 is officially out.

Compared to QGIS 2.x, there are substantial changes under the hood of the popular GIS. For example QGIS now works with Python 3 and Qt 5.
One of the biggest novelties for me is the fully integrated 3D environment.

There are so many improvements that I don’t want to mention them all here. Others have already done better:

24 Days of QGIS 3.0 Features

Intro to QGIS3 3D view

QGIS 3.0 To Be Released in February

Upcoming QGIS3 features – exploring the current developer version

UPDATE: New features and changelog

For usable binary packages we will still have to wait some hours. I will tell you here, when the time comes.

UPDATE: Binaries for Linux, MacOS and Windows are out: https://qgis.org/en/site/forusers/download.html

You have to know that QGIS 3.0 is an early adopter release at the moment.
For daily stable work I would still recommend the latest LTR version 2.18 to avoid surprises 
Next LTR will come in June with version 3.2.

For me, QGIS is one of the most important software packages in my daily work routine.
If it’s the same with you:
You can support the development of QGIS by either getting involved in the community or by giving a donation to the team.

UPDATE:
New features and changelog