I've had this type of addon for over a year that I made for myself. In January I finally uploaded to wowace after guildies have been nagging for it.
Basically what it does is finds the best target for Chain Heal. (My main is a resto shaman) I have also added in Players in X yard range, very useful for Holy Paladins Holy Radiance and druids Efflorescence. I plan on keeping it updated for MoP as I will continue to be raiding as well.
This may be hard on your CPU, but as a healer trying to maximize mana (and top meters :)), its totally worth it. I have added settings to be able to configure how often and how intensive (max amount of targets) to help with CPU over-usage.
Note: this depends on LibMapData, so with areas without map data it will not work.
This addon is also in the approval process to be taken out of "Experimental", as far as I know there are few to no bugs. The only reoccurring that I know of is when levels change (jumping down for Nef in BWD) sometimes libmapdata data doesn't register and a simple /reloadui will fix this.
Slightly off-topic, but there seems to be something wrong with your screenshot (or your UI scale), as the top and/or bottom borders on some frames aren't visible.
Thanks for adding it to the list.
About the screenshot, for some reason I haven't even noticed even when I spend all night staring at those little bubbles. I'm guessing its something with my UI Scale. I play at 1920x1080 with it scaled down quite a bit. I'll take a closer look tonight.