While 9 Monkeys of Shaolin did have a pretty big delay, Sobaka Studio have just recently announced a new release date (including Linux support) along with help from Koch Media.
The Mean Greens - Plastic Warfare, which returned to having official Linux support recently has another big update out and they've dropped the price too.
Estranged: Act II, the free game from Alan Edwardes that follows a fisherman, stranded on a mysterious island during a violent storm had a recent update to tweak various issues.
Free from the restrictions of planet Earth, the space exploration, trading and action game 'Helium Rain' from Deimos Games has officially become DRM free on GOG.
Tower Unite, a 'community-based virtual world party game' had a Linux version that was left in Beta since 2016 and eventually it broke. They've now removed it in favour of people using Valve's Steam Play.
Project Borealis, the fan-made Half-Life 2: Episode 3 is still continuing along, with the release of a second performance to test so we can stress-test their work.
I'm a big fan of Empires of the Undergrowth, an Ant colony management sim from Slug Disco Studios and after trying out the recent huge update I continue to be impressed.
ZED, the adventure and puzzle game whose team includes some of the creative forces behind Myst and many other popular games that was funded on Kickstarter has a brand new trailer and publishing partnership.
Project Borealis, a fan-game that aims to create the long awaited 3rd episode for Half-Life 2 based on Marc Laidlaw’s Epistle 3 has put out a Performance Test for Linux gamers.