I think that it is important for Blizzard to expand the game so that people don't get bored as quickly as they did with instances such as Molten Core, Blackwing Lair, and Naxx.
HOWEVER!!!!!!!!
I do not feel that it is necessary to raise the level cap as quickly as they are planning on. Also I don't think that it is a good idea to add a new profession such as inscription, to me it gives the game WAY to much of a Diablo feeling, and personally feel that it will ruin PVP for some classes.
I do however like the addition of the Death Knight, and think that it's great that you won't just be able to create one without "unlocking" it first. I don't necessarily agree with it being "pre-leveled" because I feel that takes advantage of game play, and you'll more than likely see a bunch of people running around not knowing what to do, where if you play the character from level 1 you have a greater feel for the character and are more likely to play it better.
I also think that the addition of new instances is great, however maybe not introduce them with an expansion, just add on. There are many raiding guilds that haven't even hit "The Black Temple" yet, and many more that aren't clearing instances such as "Serpentshrine Cavern". I realize that this isn't Blizzards problem, but I do feel that they should be a little more sympathetic to the amount of raiding guilds and the lack of "TOP" guilds per server.
The expansion is going to happen no matter what any of us want. And there are going to be things that people don't like about the expansion. However people who really like the game, and want to see it expand, I feel that it will be a good experience and i'm excited about leveling to 80 (Just kinda UGH about leveling 3 characters again).
I don't think they'll release this expansion for at least another 6 months, but I could be wrong. However when they released "The Burning Crusade" they did say that they were going to try and release one expansion a year after it's release. "The Burning Crusade" is about 6 months in now, and is still going strong. I just think that Blizzard might be getting a little greedy if they start releasing to many expansions to fast.
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Fragordie 70 Orc Hunter - Ursin PvP
Crowing 70 Troll Mage - Ursin PvP
Ript 70 Troll Rogue - Ursin PvP
Toujourspret 24 Undead Priest - Ursin PvP
Barfthemog 23 Blood Elf Paladin - Ursin PvP