Kinda $hitty of Canon to say the new 1DX is their "flagship" only to come out with the "real" flagship shortly afterward. 
This frustrats me....the 1dx is the flagship for spots action and events! This will be the studio flagship, both types of shooting have different needs and thus the bodies will be spec'ed in a different way (It will be some time before you have a studio quality body that has high MP and high fps and outstanding high ISO performance). If your a sports shooter then go 1dx. If you a slow shooter and wanting outstanding IQ between ISO 50-400 then this new beast may be for you!
And don't forget and don't get all pissy, but it makes sense to intro this in the flagship. I brought it up before, look at the announcement for the 1dx - and when it was actually available - vs when the 5d3 was announced and available. The tech was shared (sensor, AF), but the 5d3 body was easier to mass produce, thus that made its way to the market first. I'd guess we'll see something similar here (maybe already in process, I have been wondering if the new 6d sensor is partly based on this new sensor). Either was...If this is the 1S, then we'll probably see a 5s (at closer to d800 prices) announced in the spring and available by summer....