I shoot with a Sony Alpha. If forced between Canon or Nikon I would choose Nikon. And in fact I now own a Nikon D700, my Sony A700 is now my second body.
So let's get to the whole Canon Vs. Nikon thing. You need to understand the difference between the image sensor, that will determine image quality, and the body such as construction, and features like AF points, video, WiFi etc.
When it comes to image sensors, Canon is at the bottom of the pile. Tell your family that, in fact send them right here. Canon has been behind since Nikon dropped the D3 in 2007 with a Sony made FF image sensor, and haven't caught up since.
In their crop sensor bodies, like the Rebel, the 60D and 7D, it's very sad. Canon uses the same sensor in all those cameras, and it's not winning any awards. Only their FF sensors are really good, but still not as good as Sony Exmor sensors, also used in Nikon and Pentax dSLRs.
Body construction and features aside, Nikon beats Canon. It's so bad, that a little Sony NEX C3 for 400 bucks has an image sensor that beats every Canon dSLR with the same sized sensor. Fact, not my opinion.
There a so many Nikon pro shooters, I'm not sure why anyone would say or think otherwise. And Sony is coming up in a big way with major innovations while Canon does the same thing. Their new M series compact looks like a giant flop. So they may be number one in dSLRs, but that doesn't make them the best. Yes Canons make great images, yes pros make money with them, yes they make fantastic cameras, but the best?
The image sensor in the Nikon d600 (2100 US dollars) beats the one found in Canon's 1D X. That camera costs three times more last time I checked. How did that happen? Yes the 1D X is so far ahead in features and construction, but if the image sensor can't keep up, what does that say about Canon? That's their flagship dSLR.
The image sensor in the Nikon D5100, a Sony one by the way, smokes the one in the Canon 60D, but body build and features mean that the 5100 might not be the best camera because you have to weigh in those other factors like AF points, frames per second, AF accuracy, bracketing and so much more.
All the dSLR makers Sony, Canon, Nikon and Pentax make great glass, and all their best stuff is crazy expensive so you have to be willing to pay for that amazing glass. I tend to ignore claims of one maker having better glass over the other. Even the third parties like Tamron and Sigma have gems.