Add release notes for GPU frustum culling

release-content/0.14/release-notes/12889_Implement_GPU_frustum_culling.md

@@ -1 +1,18 @@
-TODO
+<!-- GPU Frustum Culling: https://github.com/bevyengine/bevy/pull/12889-->
+
+Bevy's rendering stack is often CPU-bound: by shifting more work onto the GPU, we can better balance the load and render more shiny things faster.
+Frustum culling is an optimization technique that automatically hides objects that are outside of a camera's view (its frustum).
+In Bevy 0.14, users can choose to have this work performed on the GPU, depending on the performance characteristics of their project.
+
+Two new components are available to control frustum culling: `GpuCulling` and `NoCpuCulling`. Attach the appropriate combination of these
+components to a camera, and you're set.
+
+```rust
+commands.spawn((
+    Camera3dBundle::default(),
+    // Enable GPU frustum culling (does not automatically disable CPU frustum culling).
+    GpuCulling,
+    // Disable CPU frustum culling.
+    NoCpuCulling
+));
+```