He sounded somewhat believable until he started going on about the amazing high ISO performance. I mean yeah the 1DX high ISO is very good.... BUT so is the D4 that he has! The 1DX high ISO is no better at all than his D4 and the 5D3 high ISO is worse than the D4 high ISO (although the extra MP on the 5D3 helps a bit in some ways). And failed to mention one thing he'd bring over from Nikon other than the shutter feel.... the dynamic range difference at low ISO where the Nikon actually is much better. So then you start thinking about all the money dangling above his head again.
I do like Canon's UI a lot better myself though.
Based on DXO tests (i.e. "on paper"), no, the 1D X high ISO is theoretically the same as the D4. However, from a visual standpoint, I've seen ISO 16000 images and even some ISO 51200 sports images from a 1D X that simply blow me away...similar images from the D4 just don't engender the same feeling of low noise and clean quality. The D4 also actually tops out at native ISO 12800, beyond which you can only select full stops with "expanded" modes. ISOs above 12800 on the D4 (and pretty much any other Nikon camera that supports expanded ISO above 12800) feel a bit "gritty." The 1D X offers full native third-stop ISO capability right up to ISO 51200, and its third stops are very clean. You have the option of using the cleanest ISO options above 12800 with the 1D X, where as you can only use 25600 (H1), 51200 (H2), 102400 (H3), and 204800 (H4) on the D4...that is a factor that cannot be overlooked, as you can always use say ISO 16000 or ISO 20000 instead of 25600 when you need more than 12800, and get lower noise results. (Same goes for ISO 3200 and 40000.)
From what I can tell, the D4 suffers a little higher chroma noise (which isn't surprising, since its expanded ISOs are a digital push of ISO 12800...read noise is getting amplified). The 1D X has lower chroma noise up through ISO 51200 (particularly in the blacks...chroma noise in the lower tones on the 1D X is very good, but it is quite visible on the D4. See here for an example: http://www.cameraegg.org/canon-eos-1d-x-vs-nikon-d4-high-iso-test/
). Luma noise is easy to clean up, where as cleaning excessive color noise can leave a bit of blotchiness behind. I've seen a number of bird photos from ISO 16000 and on taken with the 1D X, including a few ISO 51200 shots (couple shots of some geese...they were amazing, if I can find the link). The results have always been astonishing, very clean, crisp, good color fidelity.
Here are some more examples of the 1D X edge at high ISO:http://thenewcamera.com/canon-1dx-vs-nikon-d4-high-iso-war/
Artificial tests don't tell you everything. On paper, the two cameras might as well be identical. In practice, chroma noise at higher ISO settings on the D4 start eating away at detail in the shadows, where as chroma noise is quite low in the shadows with the 1D X. As a result, high ISO photos taken with the 1D X are remarkably clean and usable. An excellent example would be the NY Manhatten Island photo taken with a 1D X at ISO 25600 at night during Hurricane Sandy:
(See large version for best example of the noise quality here: http://thenypost.files.wordpress.com/2013/10/magsandy.jpg
I'm still waiting to see a comparable photo like this taken with a D4. I just don't think it would have performed as well...not with it's chroma noise.