As of 1.5 scoreboards have been implemented. Do you guys know if it would be easier to code the health displaying below the name with Bukkit or redstone? You can see an example in HyPixel's new herobrine video found here:
I would say scoreboards. I would recommend looking at the two scoreboard tutorials under the resource section.
"easier to code the health displaying below the name with Bukkit or redstone" == opinion. Some people insanely good at redstone might be able to whip this up in a couple of minutes. I suck at redstone, if you asked me it would be code.