I think Subversion still works better than Mercurial and Git for large files like media assets, Photoshop files, After Effects composites, etc. I remember Linus Torvalds mentioning big files as one of the very few potential problems with Git in this Google Tech Talk. Mercurial has a few extensions for storing large files outside a repository. So it seems they both suffer some performance degradation and/or other issues in that scenario.
Subversion, on the other hand, is being used by the current Blender Open Movie Project. I don't think they use it to store the rendered frames, since that would be at least a few gigabytes of data for each render pass. But still, with all the 3d scenes, objects, rigs, textures, and scripts, that's still one big repository with many large files.
