The list is pretty ridiculous (I made another thread up for it here:
http://www.flyertalk.com/forum/showthread.php?t=815849)
I saw in egullet a theory about how they decided on the ranking. According to this
http://www.bighospitality.co.uk/item/1558/23/5/3
We have 682 reviewers, 3410 votes (about 5 each on average). The theory was that if 100 people visited a conveniently located and famous restaurant but only half of them liked it enough to give it a vote it would still get 50 votes, if 10 people went to a less well known/harder to reach restaurant and all of them gave their vote that should mean that the restaurant was better (as it scored 100% rather than 50%) but it would still only get 10 votes.
Considering the sheer number of outstanding restaurants in Asia (and perhaps in Australia) and the small proportion of voters assigned these regions in comparison to other parts of the world, it's no surprise that they hardly get a look in.
As it stands, meaningless.