Anticipation, the 67th World Science Fiction Convention, has announced that site selection ballots are now available for downloading from this page (in English), or this page (in French). An additional fee is required of WorldCon members to vote in the site selection process (which is usually discounted from the membership fee for the selected WorldCon).
This year, voting is for both the 2011 WorldCon and the 2010 NASFiC. The 2010 WorldCon will be in Australia, and whenever a WorldCon is held outside North America, there is also a North American Science Fiction Convention, thus the double voting. Raleigh, North Carolina, is the only announced bid for the NASFiC (though a provision exists for write-in votes). For the 2011 WorldCon, Reno, Nevada, is the only announced bidder (Seattle, Washington recently announced their withdrawal from the race, after failing to secure a facilities agreement).
Ballots may be mailed in or dropped off at WorldCon this year (voting deadline is 7PM on 8 August).