aww hell no. I'd be terrified of merging into that lane with no highway divider between me and oncoming traffic. Small two lane highways are bad enough! :P
Nice! yeah, this would be preferable. If there's a catastrophe in the opposite lane, I'd really love it if it could stay over there while I'm going 70 miles an hour in the opposite direction :P
Most of the time, there's an empty lane as a separator. When it is used, they don't allow motorbikes in it just in case, but it's really no worse than a two-lane undivided road.
It's also not necessary for you to use that lane if you don't want to -- it doesn't go anywhere special :).
As a correction, as this road appears on the BBC's Motorway Cops regularly, and there was an incident featured in this weeks' episode (1): There is always an empty lane, which shifts depending on the time of day. Accidents are apparently very rare, and the speed limit is 50 mph, compared to 70 on a regular motorway and 60 on a 'normal' road.
http://en.wikipedia.org/wiki/Barrier_transfer_machine