I usually discourage against DivX and promote h.264 in an .mp4 container encoded using x264. The resulting video is non-proprietary and used to mean a higher quality video as well (which really means smaller file, basically).
However, DivX 7 is also h.264 now, so the quality argument is out the window.
I'm pretty sure DivX can encode to h.264 standard video too, now, and put it in either a .mp4 or .mkv container. People really should be doing this now.