Carbonite is an all-in-one addon that includes quest tracking, mapping and prioritization. Sounds perfect for what I want. I used it before for working through questing in Northrend (after it became free) for a few zones. It provides a running count of quests for a zone and helps pin-point the next location you should work in. Unfortunately I could not figure out how to have it pin-point areas I should go to. Of course, it also took me a week to find out where the 'unexplored area' coloration is. I was able to find the 'database' of quests and determine what I hadn't completed. What I found out is I hadn't completed any of the hunter attunement quests, or the paladin, charger quests (in Orgimmar). What I did find useful, when checking the map in Carbonite, I see quest giver symbols. As I hover over the icon, it provides me quests still to be completed. Areas like Orgimmar and Razorhill were not so useful since so many of the holiday quests are focused in this area. Other areas, like the Barrens only shown quests that I could still complete.
EveryQuest is simply a quest tracker. It keeps track of the date/time that you completed a specific quest. One bonus of this addon is that it allowed me to filter what I had NOT completed. In addition, the addon provides categories for the quests (Orgimmar, Undercity, Warlock, Seasonal, etc.) in addition to automatically pulling my current zone to show what is still left. Downside is that this addon doesn't appear to tie into others. I get a name and level for each quest, but no idea where it starts. If I could push this quest to a map, say Carbonite's, or have the data link to LightHeaded so that I can get the coordinates for the quest giver. Wait. What am I talking about??
The quest list uses your quest history to display quests from any category in game. It lists quests you haven't done in zones (ex: Borean Tundra) so you can get the achievement easier.
EveryQuest integrates with LightHeaded (Wowhead quest comments, NPC locations) so clicking a quest will open the wowhead comments for that quest. Lightheaded then integrates with TomTom waypoints to direct you to the quest giver.
EveryQuest: Quest Givers
I finished up a quest giver module that mimics the functionality of Handynotes: Quest Givers but integrates EveryQuest quest history and filtering by faction (daily quest coloring/filtering maybe later).
OK, I now need to go home and fire up that Curse tool again. I missed something.