Avid was industry standard for a while, but final cut and premiere are used more and more professionally now. Final cut x had a botched rollout ( there's a Conan video on it in fact) which led to premiere taking over their space recently, but people have come around on x a bit since the updates.
Truth be told, they all do generally the same things and it's mostly about what UI suits you and your needs. They each have their special features, but professional editors try NOT to go crazy with it unless the situation calls for it. They all have cutting, transitions, and text and for many things that's all you need. I would learn keyframes so you know how to play around with placement and if so inclined there's color correction, speed change etc. but the best editing is the editing you don't notice.
