The dungeon and raid aren't the only things that have progressed the difficulty of the game, the solo content is more challenging as well. While the respawn rates on mobs may be turned down on the Live servers compared to what they are on the PTR, the fact remains that some of these baddies are not to be underestimated. Even the new bombing run is more difficult, though less likely to kill you than the others. When Ogri'la and Skettis were first released, they were a bit of a death trap. Most people went into them in a daze, expecting to nap through the little battles like the zones we had done before. The reality was, though, that it was quite a bit harder than that. Until we adjusted to the difficulty and played a little smarter, it was death city.
Quel'Danas is about the same. It isn't incredibly difficult, but it is a step up from what we've seen so far. Tread lightly, bring lots of bandages. If you're brand new to level 70 and your gear is... well, junk, then you might want to group with some friends for the new daily quests. And uh, don't be like me and go AFK in the middle of enemy territory and expect to come back 10 minutes later unharmed. That probably isn't going to go well for you.