[jayd16]

Depends what you need. Everythin including GI is baked into the mesh.

If you want dynamic lights, you could try to bake a out the scene as diffuse and then again as normal maps. Then you can have simplified realitime illumination while still baking in AO, static diffuse lights, and the LODed mesh.

[John_KZ]

It still doesn't sound like it would work with a lot of direction-depended specular reflections or reflective surfaces.

[bananaboy]

You could probably bake out normals as part of the process (essentially generate a G buffer) and use that for specular type effects.