In todays market with Unity3D, UDK, CryEngine all offering free versions this doesnt really stand a chance.
But its free and for hackers who want to dive deep into C++ Game Engine code its a cool thing to hack with!
The nice thing is that because of the MIT license, those coding up their own engines can borrow missing pieces (such as navmesh generation, pathfinding, animation, etc.) from Torque. I really like this move.
Guess it's time to start wearing my old GarageGames t-shirt again. Unfortunately, college was a few years and a few pounds ago...
Torque did build and run (In-game editor an all) on Linux back in the day, although support was always iffy (not sure if that's pre-Torque3D or not) - maybe open-sourcing will bring out some Linux hackers to shore that back up.