As part of the Energy Policy Act of 2005 that Congress passed last year, Daylight Savings Time will be extended by four weeks.
One of the rationales behind DST is that we leverage the longer daylight hours in the summer months to minimize the need for artificial light. This operates off the assumption that the time people spend at home in the morning is less than the time spent when they arrive home in the evening to the time they go to bed.
It's possible, if not probable, that the savings of these four "new" weeks will marginal. For one, it's also based on the assumption that with good weather and extra daylight, people will spend time outdoors. DST doesn't work if everyone goes home and watches TV - something they are more likely to do when the weather is cooler (and it presumably is during the new weeks). It's also generally offset by shorter daylight hours during these weeks.
But putting aside the rationale for a moment, Charlie reminds us that any energy savings may ultimately be offset by IT costs anyway.