Both brands are its highest in photography but other camera brands like Sony, Lumix (Panasonic), Olympus to name a few are also good. But the two (Nikon and Canon) are the most popular. Each of these two brands have its own Pros and Cons. For starters, Nikon produces a different color perspective while Canon has its own color (May joke nga kami dati yan eh. ito yun "Pinili ko ang Nikon kasi madiliw ang lumalabas na kolor sa imahe gusto ko kasi madiliw, kaya nga logo ng Nikon dilaw. Tignan mo yung sa kabili (refering to Canon) pula ang logo nila kaya mapula din kuwa nila. Nasa logo yan eh") Back to topic. Nikon is more user friendly while Canon is a bit more complicated but both brands are excellent once you get to it. Both brands are its perfection today. You the aspiring photographer or a casual shooter decides which brand suites you.
If you are on budget try Canon 550D (If you can wait the Newest Canon 600D) or Nikon D90 (If you have more budget, The Nikon D7000) . For me I don't like the Nikon D3100 (Save a few more then get either D90 or D7000). You decide. For example you decide to get either the Can's 550d or Nik's D90, try to hold it on your hands first, feel the buttons, weight it in on your hands then take a snap shot then hear the shutter sound. Once you know you had choose the perfect camera then buy and then don't turn back. Mahirap na mag shift ng brand.. hehe.. Overall, nasa sayo na yan.. pick with confidence