As Bigmouth has noted on his blog: http://eyemsick.blogspot.com/ TPTB have mentioned "antipodes" in a couple of their last interviews this season. Antipodes are geographic locations that are diametrically opposite to each other through the center of the earth. Check out his great post and references on it.
After reading that I got curious and did an image search on antipodes and found a Google map for finding them. I put the arrow on Tozeur, Tunisia, where Ben's hotel was (not necessarily where he landed) and the bottom arrow landed at the antipode as shown, to the right of Australia. It's not exactly at the "4.815, 162.342" coordinates, but a bit south of that. Going to a "4.8xxx..." point takes the antipodal arrow to the far south of Nigeria. Not a bad proposition for explaining Yemi's small plane getting to the island, although that's too far away for Ben to be riding a horse to his favorite hotel with no provisions. But...is Tunisia the antipode for the island's position in 2004, or for its location after it "moved" and spewed Ben out to the antipodal point in the desert?!
I thought that it was interesting to find a map that could locate the exact antipodes for us, so that we wouldn't have to guess, in case this concept is a key to locating the island.