Having, and hiring, writers, artists, designers, scripters, etc, to work on pre-production for other projects does not take anything away from the programmers working on the Linux port of the engine.
There isn't anything going to be revealed about a new game until E3.
The Linux version was always going to be started after the Mac version was done. The amount of time and work required was much longer than anticipated. That is part of the development process.
