No, using walls to position mobs is just fine. The dungeons are designed with their terrain and geometry in mind; the designers expect you to use whatever advantages they give you in order to defeat the encounter. Things like Halls of Reflection are a good example of this.
There is some gray area, however. In The Burning Crusade, there was a log that you could stand on in the Archimonde raid boss encounter that would avoid the fire he laid down. There was also the side of the mountain that you could stand on and, with careful positioning of the tank and groups, avoid many of the harder mechanics of the fight. Was this a case of direct exploitation of the game or just intelligent use of the geometry of the environment?
While it's still hotly debated amongst some, the overall opinion (at least from Blizzard folks we've heard from) is that if the tricks avoid the mechanics of the boss fight all together, then it's not exactly cool. So something like positioning mobs via the walls in HoR is OK (because you're still dealing with all the mechanics of the mobs), but sticking Archimonde at the bottom of a hill is not (because you're avoiding fire for all but the main tank).
Remember, though, that there's no definitive answer; at the end of the day, it's up to Blizzard to decide what's exploitation and what's not. Just hope that you fall on the good side of it.
When's BlizzCon 2011?
Blizzard hasn't announced it yet and won't for a long time.
Is there a way to play WoW not on the official WoW servers?
Yes, but it's flat-out illegal. Don't do it.
Does anybody know what or if we will be getting a pet this year for the sixth anniversary of WoW?
No idea, yet. We'll just have to wait and find out.
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