The dimensions are a little different, Blackberry measuring 120 x 62 x 11.5 mm and weighting 135 g, while Samsung measures 119 x 58 x 13 mm and weights 125 g. So, there is a little difference, Blackberry being a little heavier and at the same time bigger.
Regarding the display, besides the fact that Samsung's screen is AMOLED, Blackberry has a 3.7 inch TFT capacitive touchscreen, 16M colors with 480 x 800 pixels, while Samsung has a 3.5 inch capacitive touchscreen, 16M colors with 480 x 800 pixels. That takes us to the camera chapter, where Blackberry wins, with a 5 MP, 2592х1944 pixels, with autofocus compared to Samsung's 3.15 MP, 2048x1536 pixels, with LED flash.
Another difference is the CPU memory: Blackberry is equipped with a 1.2 GHz processor, wile Samsung has a 1 GHz processor. So in the end, I would choose Blackberry Torch 9850 instead of Samsung Exhibit 4G, but that is only me.