Upload & Sell: Off
D4 with a Lexar 1000x CF card will do 66 continuous frames at 10fps. My guess is the 1DX at 10fps would probably be in the low to mid 40s? Two seconds of additional continuous action is considerable though.
The question always comes up: why would anyone need to shoot continuously for that long? At least in my shooting experience, there can be times covering sports when a play develops into one that is much longer than anticipated. For example, in football, focusing on the QB as he drops back and shooting him doing so (perhaps anticipating a sack) as he throws or hands off, then continuing to shoot the play, which becomes a long run or catch and run for TD, then photographing the reaction/jubilation afterwards. This can easily spread out over 5-10 seconds of nearly continuous action, is difficult to predict and therefore difficult to conserve buffer space. Shooting Jpeg helps, and sometimes is the better option.