The post that really grabbed my attention was this one about warlock complexity in Cataclysm because it highlights an extreme form of something we've talked about before, the design philosophy that argues for increased complexity in a character's suite of abilities. In its simplest form, it can be summed up as the hitting buttons is fun argument, although at the extreme Cyn describes for warlocks, it becomes a game of if X, then Y that resembles programming your first computer in Basic. If you remember making a chain of dirty words scroll on a loop up the screen, congratulations on being old with me.
Cyn's comparison of the destruction rotation in Wrath and Cataclysm shows a rotation with seven elements mushroom out to one with 14 elements to remember and consider. That if X, then Y flowchart just got as complex as a subway map. In my experience, all DPS rotations in general have a little bit of this kind of gameplay nowadays. The difficulty is in hitting the sweet spot where the rotation is designed so that random elements or procs serve to liven up an otherwise predictable set of abilities (providing the fun in the hitting buttons scenario) without making a rotation so complex you need six to seven addons to help you plot it out.