As someone who no longer games, my Desktop is rotting. I can't use a computer sitting outside work anymore, I prefer lying in bed working so my Macbook takes the cake here.
Desktop is great for cost effective power, upgrade ability and robustness and I also use a laptop for mobility. Cloud storage and Apps really help too so I don't need such a powerful laptop.
Laptop is the best solution for me. I prefer the laptop for convenience. However the desktop is technically the best resource compared to laptop depending on software I use. Other versions of software work better on desktop than laptop.
If I can only choose one, then it has to be laptop. Much more versatile and you dont need a 15/17" screen to have power, cases in point are lenovo X260 and Dell XPS13's.