Here is a link to a US Department of State website that details the proposed changes to passport requirements.For people driving back and forth, the requirements won't be in place until 2008.
Here are two links to visit:
Timeline: http://www.travel.state.gov/travel/cbpmc/cbpmc_2224.html
General Info: http://www.travel.state.gov/travel/cbpmc/cbpmc_2223.html
Don't let the rumors misinform you.
Justin