i am free lance photographer for world papers and local companies so i have had experiance with a lot of nikon and canon cameras, and your all round best bet is using Canon.
I love my Canon's because they put the important adjustments, ISO, DRIVE, WHITE BALANCE and QUALITY, right where I need them. I don't need any menus to tweak them, and I need to adjust them many times each day as the light and subjects change. Nikon hides more of this, like manual and trimmed white balances, in menus, which gets in my way and is extreamly difficult to use when you need it to work in emergencies or difficult times haa.
I'm enthusiastic about Canon's gear today because it's so much better and cheaper than a few years ago. Life was tough in the manual focus days. Even the crappy Nikon & Canon zoom lenses today are much better than the classic manual focus ones I used before. Nikon & Canon has never given me so much as a free hat, even for all the free publicity I give them on them when i review camera's in magazines.
I could go on all day about the differences in cameras and the pro's and con's but your best bet is a Canon, try a 5d or 1d if you can reach that price range and ask if the shop your buying it from the recommended lenses
BUT... you need to go and try the camera's, well at least get hold of them as you may find them too small, big or heavy or even awkward for you.
good luck with your cam and new job

xxx