As far as I was aware their product range has almost exactly mirrored Canon's up until the launch of the V1 and J1 late last year.
Well I (respectfully, and partly) disagree with your statement. I think the LL reviewer was mostly thinking about the D3, which was the first Nikon pro DSLR that really put Nikon ahead of Canon
for a category of users (spectacular high iso performance at the time of its release), whereas the previous D1 and D2 series were not very good value against the Canon offering of the time, and many thought that Nikon was "going down". The D700, as a "baby D3" has also been extremely popular among pro and enthusiats. And the D3S significantly improved what was already Nikon's strong point by offering even higher low light performance, along with the very advanced autofocus system of the D3.
In the last few years, Nikon has mostly been about great autofocus / high iso, while Canon has been more about resolution and video (I'm generalizing, it's not always true, and the differences aren't always significant between two similarily priced models).
What I mean is, I don't think the LL reviewer is saying that Nikon has been better than Canon in the last five years, but that they were dangerously lagging behing and have been able to get back on track and now are competitive against Canon.