This is what Dustin from Origami Team said about it:
It is true that most of these devices won't rotate but ultimately it is something the OEM could choose to support. Windows however doesn't exactly work great in a resolution like 480x800 so on devices that do rotate you need to expect a fair amount of usability issues if you play around in the UI too much. I can image a lot clipped screens, etc. in a portait resolution on these devices. It is true the LS800 rotates I belive in 600x800 mode, but you do run into various issues when running in that resolution.