Yes it is. You can either have a lithium battery or use the adapter and use AA. A very smart move as far as I'm concerned. Image quality is rated as being even better than the K5.
And Paul's right, If you look around a K30 body ( I already have the lenses) is about the same or less than the HS50 launch price.
Love dat Fuji
Pentax K1000, Pentax sf7, Pentax zx-50