New Gaming HDTV Specs to Look for or Pitfalls

[itgl72]

I'm moving into a new home. I'm in the need to pick up two new HDTVs, one for family room (hung above fireplace) and one for my gaming room/office.

Move in time is coming quick, and I'm looking at what specs I really need to look out for to get a good quality gaming experience on a HDTV connected to an Xbox One and Wii U (some PC steam streaming may happen as well)

From your experiences, can you share what you think I must look for?

I'm researching as well and reading up on things like input lag, and game mode, etc.