Many of the photographs in my living room have been on display for over 20 years, with no visible fading. As long as photographs were properly processed in the lab (rather than skimping on the time in the final 'fixer' chemical, as some cheapo labs do), and they're kept out of direct sunshine, they should look fine for decades.
However Ratter15's suggestion of displaying copies (with the originals stored somewhere dry and dark) is a sensible one. You can also buy a spray-on product which protects photos from UV light but it's expensive and probably unnecessary.
Chris