A Google Web Search Help thread reports that now Google is rolling out the left hand navigation design to iGoogle users in the UK and France.
I believe the US had the new, left hand navigation for a while now. Many users miss the old tabs at the top and we discussed a way to bring the top tabs back. So, if you are in the UK or France and you miss the old tabs, check out that article, I hope it still works. mooredc54, in the thread, discusses other methods to get the old tabs back.
Forum discussion at Google Web Search Help.