The Tank Shortage is a topic that's come up a few times before, though thankfully, since the release of Wrath, Death Knights have more or less solved the situation. But the issue facing us now is just as dire: a Healer Shortage. Ghostcrawler acknowledges that there may be such a shortage on the forums, and he gives two reasons: first, lots of people are still working their way up to level 80, and the majority of healers may still be leveling through Northrend. And second, they've beefed up and changed a lot of DPS builds lately, so many pre-Wrath healers may have respecced DPS to try it or to level a bit, and haven't gone back yet.
Later, he backpedals a bit -- not everyone is experiencing a healer shortage, and while he's already told us Blizzard is working on ways to make healing more "fun," he also points out that some people enjoy the whack-a-mole game. Still, just because a problem isn't affecting everyone doesn't mean it's a problem: it's true that lots of groups are having trouble finding healers, and lots of healers would rather not watch health bars all day.
We're very curious to see what changes Blizzard might have in mind for healing -- we discussed quite a few on the healer podcast a while back, including making healing spells a little less attention-intensive, and giving healers some UI ways to keep their eyes on the fight rather than their party members. And of course, if the rumors are true, we'll hopefully have a new healer Hero class to come and fill in the blanks. GC says this isn't a matter of tweaking things in one patch, so we are definitely a few patches away, but there is hope for healers on the horizon.