Long time lurker here, first time poster...
I'd add to jrista's observations that the implementation of CFast here is probably not for burst rates anymore, but more for video. As a current 7D owner, and a user of MagicLantern (or whatever it is now... TragicLantern maybe?), the card write speeds are far too slow for RAW video and generally pretty iffy for higher-bitrate H.264, so any card write speed improvements would probably be for video, not photos. Even the 1DX has a buffer that will eventually fill up, and if Canon would try to design any camera to be able to sustain a burst, I'd expect them to work on the 1D series. I certainly wouldn't say no to a sustained burst on a new 7D though!
I think you need to start posting, as you seem to know what you are talking about. We can all benefit from your knowledge.