Depends if you know anyone else that has one, or want to play exclusives. The only game to date that's cross-play with PC is Rocket League
Some of the communities stay alive longer on the XB1 such as CoD games and others like Titanfall. Also, you can buy preowned games and trade other physical copies where you can't really with a PC. Conversely you're stuck using a controller for everything, depending on the type of game this can be a benefit or a hindrance.
What kind of games do you play and what did you have in mind?