Casuals dominate the World of Warcraft. It's a game that's set up for people to burn away excess time they have watching pretty graphics and sound effects. Anyone who really wants a serious game and doesn't care about the fluff is better off playing Go or Bridge. As such, the bulk of the Warcraft population simply is not going to raid 6+ hours a week, nor are they going to make a significant dent into the heroic-mode raids.
Blizzard has recognized that casuals are their main customers since at least Wrath, and I'm guessing The Burning Crusades. They often toss statistics around about how RidiculouslySmall % of players ever even saw Ragnarok at level. So what are they trying, and how are they doing? MMO Melting Pot asks, and here is my answer. Here are the ways I see to burn time casually, and how they are working for me.
Leveling alts. This is my favorite thing to do once my main character is maxed out. In addition to there being three different roles of play (damage, healing, tanking), there are several different styles of resource mechanics (energy, mana, runes, cooldowns) and different styles of priority management (procs, synergistic spells, long cooldowns). Playing with different classes and specs keeps me amused for so long that there's not much else I expect to spend time on in Warcraft.
Experiencing more content. The new low-level zones are quite fun. However, I don't spend much time on them so far. The main reason is that it's very difficult to keep a toon at just the right level to experience the content. It's a little too brainless to walk through a zone with tiny little enemies that die when I breath on them. This could be fixed if there was some simply way to intentionally weaken a character when entering a zone. I'd love it if I could play a zone and set my character's effective level to that of the zone.
Dailies. There have been some compelling clusters of dailies, but they are the exception. The best I've seen were the tier-9 dailies, the ones that went with the jousting tournament. While the tier-9 dungeon was the pits, I thought the dailes were well done, and I did a lot of them. Ever before and since, however, I haven't gotten into them. The Tol Barad ones I am finding to be particularly grindy and boring, especially the ones on the northern island.
Crafting, and secondary professions. I find the professions themselves okay. Blizzard has done a good job of making all umpteen crafting professions different and useful. However, leveling them is a total bore. Going through 524 iterations of looking up a recipe, finding out the mats, buying them on the AH, is just not fun. I wish they could come up with something like fishing, where higher skill is important but not overwhelmingly so. For example, they could let you craft anything, but with a lower skill require you to add some extra components.
Fishing and archaeology. I used to really like fishing. Archaeology, in my opinion, is like fishing but better done, because you end up moving around and seeing different locations. However, despite having the Salty title, I've dropped out of both of these in Cataclysm. Partially this is because the dungeon finder is so good. Partially, though, the new bloated fish are just too hard to catch, and archaeology is a bit too slow to level for my taste. I can't see myself really going back to these any time soon; there are enough specs and zones that I will have plenty of things to do between raids.