In the age of free AAA game engines, where does our open source engine stand?

erlend_sh writes: The game development industry just got hit by a tidalwave of free. Unity 5, Unreal Engine 4 and Source 2 all give away their flagship product for free now. They’re all different brands of "free", but who cares? The average game developer certainly won’t.

Which left us wondering: Are hobbyist-run open source game engines like jMonkeyEngine still relevant?