I have the 7105t and my girlfriend has the 7290. The 7105t has a better screen, the blink led indicator, and the speakerphone. But, the 7290 has the better keyboard, the trademarked blackberry size, for some reason gets better signal, and whenever you use aftermarket software for pictures, my girlfriends phone has a couple of more options.
My girlfriend likes the size of hers, but I like mine because it is almost the size of a regular cell phone. Take those into consideration and make your decision.