If you're considering healing seriously and don't use an alternate unit frame to the Blizzard basic UI, then rush read this post by Keeva on Tree Bark Jacket. It's an illustrated (a lot, and I mean lot of screen captures) comparison between Healbot and Grid, the two most used healers UI replacement frames.
I personally use Grid on both my paladin and priest, and I really like it. I've recently discovered all the options that you can use to check your buffs on the raid, it's really a huge help to maintain your shields & hots and other short duration buffs up. If you need help with grid configuration, I like this post by Kae on Dreambound.
In case you don't know where to find them, give a look to the curse add-on website.
Much thanks to the druid blogging community that is so active.