For watching sports you're going to want the 120hz refresh rate as that higher rate will reduce motion blur and the "jaggies" you see around moving objects.
p.s. An LED television cannot be an LCD and it's Blu Ray. Sorry, just being a stickler
Hope this helps!
I'm about to receive delivery on last years model Samsung 52" led lcd with 60hz refresh rate (great buy) and am considering changing to the Samsung 52" led (LN52A850) for the faster 120hz refresh rate (about the same price). I've also ordered the Samsung Blue Ray home theater system. The tv will be connected to cable for sports and blue ray for movies. Question is, which tv would be better for the intended used.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic