The ioDoom3 project was announced by the ioquake3 developers immediately following id Software's announcement of the Doom 3 source-code drop. While backed by developers of ioquake3 and on Icculus.org where the the ioq3 engine continues to be wildly-used and deployed in various open-source titles, the ioDoom3 project hasn't taken off nearly as much.
The ioDoom3 Git repository shows the minimal activity that the forked id Tech 4 code-base has seen in recent months. The ioDoom3 mailing list and Wiki have also been very dry in recent months.
Slightly more active than ioDoom3 is the Dhewm3 fork that was announced within the Phoronix Forums by a lone developer. The dhewm3 Git repository at least saw a handful of commits last week. The last major exciting work that Dhewm3 saw though was back in July when SDL 2.0 support was added to the game engine.
Another surviving open-source Doom 3 fork is Dante, the work done by driver developer Oliver McFadden that mostly comes down to graphics improvements for the aging game engine. Dante received EGL support, Android, GLSL and OpenGL ES 2.0 support, and a new GLSL back-end. The Git repository shows the last commits there as from October.
Meanwhile we're still waiting for id Software to release the Doom 3 BFG source-code that was approved for GPL release one month ago to the day. The company will not be releasing a Doom 3 Linux BFG client but with the code's availability it should be possible to easily port the changes to Linux if there's still open-source developers around interested in the id Tech 4 engine.
Separately, a major Linux game port will be announced soon.