I record programmes off Sky to watch later, but rarely watch it "live". The rest of the time I'm either streaming from Netflix or Amazon Video.
Their idea of "Fluid TV" is interesting i.e. the ability to pause on one device and pick up on another - not that I think I would make much use of it however.
The new box has the ability to record four channels at once though, which in my house would come in useful.
I guess it will come down to the price, and I expect it to be seriously pricey.