Isaac said:
Canon went as far as III in their lineup with the 1d series.
You forgot the 1D Mark IV.
Calling it the 5D X would make not make sense if you take Chuck Westfall's explanation for the X:
- X for extreme (X-treme) performance
- X for cross-over (X-over), since this represents the merging of Canon's two pro digital SLR cameras, the higher-resolution EOS-1Ds Mark III and higher-performance EOS-1D Mark IV, into a single next-generation model
- The Roman numeral X, as in 10, because the EOS-1D X represents the 10th generation of pro-class SLR from Canon since the F-1 debuted in 1971
If Canon would regard the 5D series as pro-class, then only the last one would apply.
So my bet is on "Canon EOS 5D Mark III".
Funny that only the 1 series has the dash between "EOS" and the digit.
By the way, am I correct in these 10 generations?
[list type=decimal]
[*]Canon F-1
[*]Canon New F-1
[*]Canon T90
[*]Canon EOS-1, 1N and 1N RS
[*]Canon EOS-1v
[*]Canon EOS-1D and 1Ds
[*]Canon EOS-1D Mark II and 1Ds Mark II
[*]Canon EOS-1D Mark III and 1Ds Mark III
[*]Canon EOS-1D Mark IV
[*]Canon EOS-1D X
[/list]