Documentation needed for crossing the U.S. border after June 1st, 2009
Hi guys
Some information about crossing into the states in terms of I.D. From what I've found, it sounds as if you will still be able to get into the states without a passport, but going the route of using your birth certificate and the driver's license you currently have will not be a valid way to do it anymore. This is due to the "Western Hemisphere Travel Initiative" - WHTI.
On the U.S. Customs and Border Protection's website, it tells us what documents we would need when entering in from outside of the U.S.
http://help.cbp.gov/cgi-bin/customs.cfg/php/enduser/std_adp.php?p_faqid=74
On June 1, 2009 all U.S. and Canadian citizens who are 16 and older traveling between the U.S. and Canada, Mexico, Central and South America, the Caribbean, and Bermuda by land or sea (including ferries), will be required to present a valid passport or other alternative documents as determined by the Department of Homeland Security. U.S. and Canadian citizens who are 15 years old or younger will still be allowed to travel with just a copy of their birth certificate, as will teens between the age of 16-18 if they are part of an adult supervised school, religious, cultural or athletic group
On the Canadian Border Service Agency's website, it also defines what documentation you will need for what mode of travel you will be taking and provides an understanding of what those documents are
http://www.cbsa-asfc.gc.ca/whti-ivho/doc-eng.html
In short, it's best to get a move on if you don't have the required documentation just yet.

Moved to the "For International Attendees" so it doesn't get lost. Thanks for the update!