One type of light that is not listed and may be in interest of many cyclists is 2.4w micro halogen like this Cateye HL-500II.
I have seen a few varieties from other company but don't know the difference between them. At least I can tell you from my unit, it is(does)....
* Output is more intense than 1w LED(PlanetBike in this case) 4 times as much(guesstimate).
* Output is more intense than 5w Halogen(very disappointingly, about the same intensity as 1w LED)
* Once piece unit. Important to some cyclists.
* Relatively long burn time with AA NMH batteries(2300mah). 3.5+ hours(by real world test).
Only draw back I can think of maybe the life of the bulb which I haven't test it to burned out yet.
I'll post the photos of intensity comparison against 1w LED if anybody interested.