On January 1st, 2005, California Assembly Bill 2628 was signed into law. It allows some hybrid cars to drive in the carpool lane, even if the vehicle has a single occupant. However, carpool lanes are funded by federal grants, and the federal government threatened to take away their funding if California allowed this law to take effect. The implementation of the law was postponed indefinitely.
The opposition to California's law was spearheaded by domestic auto manufacturers, who consider AB2628 a "buy japanese" bill. This is because domestically manufactured hybrid vehicles get far less miles-per-gallon than the Japanese hybrids, and don't satisfy the requirements of the bill.
In a positive development, the federal transportation bill which was just signed into law by El Presidento Nepotsis (nsfw), allows hybrids in federally-funded carpool lanes. The California ARB (Air Resources Board) have already updated their website, adding a number of hybrid models to the list of single-occupant vehicles that qualify as able to drive in the carpool lane.
What's the effect on hybrid-driving commuters like myself? Well, here in southern California it means that the commute might be 5-10 minutes shorter. Yay. Now it should only take 55 minutes to drive 32 miles, instead of the usual hour.
The importance of this law taking effect is not about the commute however. It sends a message to domestic auto manufacturers, who have been working overtime for years to prevent mass-adoption of fuel-efficient and environmentally-friendly cars in America: Fuck you.