Personally, I usually have at least a red blinky on my road bike if I’m riding alone. Knock on wood, I haven’t been hit yet, so maybe it’s working.
Seems NiteRider is thinking the same thing and wants to promote using lights on your bicycle even during the day. The thinking is the extra attention (particularly if it’s blinking) alerts all-to-often-distracted drivers to your presence. So whether it’s their lights or someone else’s, they just want you to use more lights. They’re also giving away one light to a Facebook fan every day week until March 1, 2012.