lighting efficiency and fuel savings

I noticed the entry below talked about putting in LED street lights and the big savings we'd get from implementing them.  As far as WhatisMPG.com goes on that we think it's a real good idea in relationship to saving energy but on the other hand what kind of lighting will LED light give off?  Is it going to be as efficient in lighting things up?  This brings up all kinds of concerns with safety issues from a cursory glance from personal perspective.  It seems like we need more research in this area before we jump the gun on changing lighting that lights up public roadways.  LED lighting might be more fuel efficient but I am certain that the spectrum of light they put off is much different that the existing lighting.  So, at this point you could say we're on the fence as far as this subject goes.  Just another view point.