After many years of using compact P/S cameras, I've decided to upgrade to a DSLR. I've been reading "Building a digital SLR system" and the author recommends Canon as the top choice to go with. After doing some research, I've found that Canon and Nikon are both tied with about 39% of the market share in DSLRs (not sure how the pro or enthusiast numbers stack up) right now, but that Nikon has been gaining on Canon in the past years. So is Greenspun's recommendation to go with Canon as valid today? Even though I won't be using their expensive cameras any time soon, I'm curious where the majority of pros use Canon or if the numbers are split evenly. I have some ambitions of doing professional photography (eventually), so I'm wondering if choosing to learn Nikon or Canon's system at this point makes much difference. Maybe getting a job as a photo assistant is easier if you can pick up a Canon and already know how to use it compared to Nikon? Also after researching rental options, it seems like Canon has a slightly better lens and rental options in my area, but it's hard to say for sure. I'm also considering Pentax and perhaps Sony because it seems like their in camera IS systems might allow me to save some money on lenses. I've heard that Pentax offers a good price to performance ratio in particular for their lenses. Not sure about Sony as I haven't researched them as much. Lack of places to rent Pentax or Sony gear seems like a big downside though. Pentax's financial woes also seem like a downside. If they get sold off or if they stop making DSLRs like Kodak, can you still get your camera serviced? Also it seems like it would be harder to get taken seriously say shooting a wedding if you go with a brand that isn't Canon or Nikon. Any thoughts? Edit: Also, after reading the very old Canon vs. Nikon page , is any of this information still accurate? I'm wondering if Nikon's advantage with wide angles and macro and Canon's with big long image-stabilized glass still holds true.