Is there much difference between the two?
Yes and No. They can accept 1080p signals, but not display them natively
Between the Sharp and the Sony? Or 720p and 1080p?
There are differences between the Sharp and the Sony, but what i prefer and what you prefer may differ.... the Sharp edged it in colour and detail for me, but tbh you'd be quite happy with either i'm relatively sure!
Sorry if my long range crystal ball binoculars aren't working today.
As you said, you can't buy it here today.
Sometimes i get worried in this place:
It may not be out over here yet - coming later this year, but still.....