Remember that leather is skin so make sure you use a good leather conditioner on it from time to time. We had a beige leather sectional that looked great at first. Unfortunately, the dye from peoples' blue jeans began to turn it a weird grey color on the seat cushions (so get a dark color!). It was uncomfortable to sit on in the summer here in the south (think sticky sweaty) and we had to cover it during those months. After several accidental punctures from our old cat and a ball point pen in someone's back pocket, I tore the leather off and re-upolstered it with a thick chenile. It looked great for about 2 years and then the whole sectional seemed to break down. I think the leather somehow made it sturdier. I'd love to get leather again, but our new kitten is a ninja cat and I know it would be a disaster!
I always preferred the feel of fabric but I have a bunch of cats and want a white sectional. When I get it, it will be leather. Getting pet hair out of fibers is a nightmare of constant upkeep. In this regard, leather would be a dream.
I will say watch out for "bonded" leather "deals." It's nothing more than scraps of real leather melted down to make a weird amalgam. Kind of like hamburger filled with pink slime. Just say NO.