Allwinner advertises their A10 SOC as supporting HDMI 1.4 and 3D displays, so I think 800x480 refers to the 3d hdmi output.
This one seems pretty good.
I could swear that last week, the yinlips page
for this had images of people playing 3d games with blue and red anaglyph glasses on. Got a nice laugh out of that
For what it's worth, the smaller screenshots on that page are almost 480x272.
Almost ordered one on impulse just now, but thought better of it.
I'd kill (or pay $20 more
) for a capacitive touchscreen on one of these smaller devices.