the landscape is because they have lenses by carl zeiss which has that added feature of reducing glare. the non-landscape ones are just regular lenses (still good) but has more of a glare when you drive/wear them.
also on the landscape lenses, you can see a small [x] on the lenses themselves in the corner.
the extra cost is because those lenses are really great.
Thanks Nako! I think I like the landscape ones more..I hate glare..LOL. did you buy a pair when you were in SF??