As of January 1, 2011, standard 100-watt incandescent light bulbs are being phased off of California store shelves. Bulbs that were manufactured before January 1 or already on store shelves can still be legally sold and purchased, but no more of the low-tech, energy sucking bulbs can be brought to market in California.
The California Energy Commission is quick to claim that this is not a "ban" on incandescent bulbs, but rather a new energy efficiency standard. In fact, it's the same standard that was passed by Congress and signed into federal law by George W. Bush, which will go into effect on January 1, 2012. As is so often the case, California legislators decided to get ahead of the rest of the nation.
According to the CEC, "California has enacted the federal standards one year earlier to avoid the sale of 10.5 million inefficient 100-watt bulbs in 2011 which would cost consumers $35.6 million in unnecessarily higher electricity bills (Source: PG&E Case Study)."
As for the New Year's roll-out date, Renee Montagne pointed out a quirky coincidence on Morning Edition: "So incidentally, it was on New Year's Eve in 1879 that Thomas Edison first demonstrated his newfangled incandescent light bulb to the public."