It's a good deal if you already own Sky but a little dissapointing if you don't. This looked like a promising service (for me personally) when it was first mentioned as I can't have a Sky dish at my flat and so this would be the perfect way to get the Sky Sports package (I miss cricket and football ). Unfortunately the subscription price and channel availability put my off. I'm sure they will develop it in the future and if more channels get added then I might be pursuaded to go for it.
Subscription cost is identical to normal Sky. Channels are upgraded daily not futurely. :)