I believe that as of December, all 18 volumes of Naoki Urasawa's Monster will be available in English. I've ready only one volume, but some day I'll get the rest.
As expected, they were waiting for the conclusion of Monster to bring out 20th Century Boys. In January 2009, the first volume of 20th Century Boys will be out.
In addition, Viz has decided to be super awesome. Also in January Pluto volume 1 will also be released. Urasawa x Tezuka. How can you go wrong?
Oh, for people who don't realize, you order comics two months in advance to get awesome discounts. Now is the time!