Not that I'm all that likely to produce many, but sometimes it is the shortest blog posts that make you think most. Rohan from Blessing of Kings posted a short update, saying "So I'm guildless, and have been trying to PuG as Retribution. I've done a couple of heroics, but it's quite hard to get groups as DPS. There's a significant healer shortage. It's driving me closer and closer to Holy. I don't really want to, but going Holy just makes so much sense." Now this is interesting because it reveals a completely different attitude to being a healer than I have.
Me, I like being a healer. I even leveled my undead priest with a holy / discipline build to 80, just so I could heal the occasional group while leveling, and only ever played shadow in betas or on my alliance priest. I very much enjoy healing in PvE, both in small groups and in raids. Don't get me wrong, I'm fully aware and enjoy the advantages of the healer shortage, being able to get a group or raid slot easier than most other classes. But I'm not playing that class and build just to get invited. I'm just being lucky that my personal preference happens to coincide with what everyone else wants me to be.
But I do understand the "I don't really want to, but going Holy just makes so much sense." problem, because just like Rohan I prefer cooperative group play to solo play. Retribution paladin is great for solo and PvP, but for groups players are divided into three classes: tank, healer, random; and a retribution paladin or shadow priest would find himself in the least favorable random class. Yes, a group only needs 20% of tanks, and 20% to 30% of healers, which makes it appear as if random dps classes with 50% to 60% would be most in demand. But on the supply side there are far more than 60% of players that play dps classes or dps builds, so in most cases groups find the dps easily and then have problems getting a tank or healer. Since WotLK the tank shortage has receded a bit, due to some death knights tanking, but that only increases the healer shortage. So for people who prefer the dps build, but have a healing build available for their class, there is a difficult decision to make: dps and solo mostly, or heal and group much more.
And Rohan says he is unguilded. Getting into a guild is a *lot* easier if you are willing to heal. Even me, casual as I am, once got picked up by a serious raiding guild at level 60, and got up to the end of BWL with them, just because of the healer shortage. I have no doubt that Rohan, who knows the paladin class better than most, would make an excellent healer, and would have no problem at all to get into the guild of his choice, if only he wanted to heal. On the other hand, he doesn't appear to really want to heal, so in the end he is screwed either way: Play a way he doesn't like in groups / raids he likes, or play the way he likes in hated solo. If your personal preference of how to play isn't all that compatible with your personal preference of what to play, you have a problem.
So as I mentioned in the previous post, I think that Blizzard will add a healer hero class in the next expansion. And before that they plan to add dual spec, allowing healers to have both a healing and a dps spec. But will that help if people simply don't want to heal? Or are just plain bad at it? I'm not underestimating the skills of non-healers in a raid or heroic group, but I can assure you that the skills a healer needs to have a *very* different. You can't just say "today I heal" and expect to be very good at it without much practice. The best thing this can possibly achieve is some more people realizing that healing isn't quite as easy as everybody else seems to think.