It happens, but I'll try to touch upon each of your points and maybe give some small amount of insight and reassurance that they're all points we're either aware of or actively working to resolve.

Regarding spec viability we would definitely like to see every spec at least partially viable, that doesn't mean however that each spec will be equal in a very cutthroat PvP environment like the arenas. A prot warrior or shadow priest or what have you should though be able to jump into a battleground or arena and be able to do something with some small amount of success. How much success that should be is really the question, but our general philosophy is that we're ok with some specs not being as viable as others, we sort of have to be.

There's a synergy within the classes for PvP, as well as PvE, that doesn't lend itself to a model where every spec is exactly the same, exactly as viable as the other, in every situation. At that point we start watering down classes, watering down abilities, copy and pasting, the focus of the game is lost, dogs and cats are living together... mass hysteria.

Moving on to battlegrounds I don't believe we've ever stated that we have fewer maps to keep queue times short, that's not an issue. The issue is the amount of time it takes to create a battleground, and balancing that work time with other areas of the game. Battlegrounds are very labor intensive, Warsong Gulch which is probably the smallest of the battleground maps still has some terrain issues here and there. Playtesting, balancing, making edits, all require a very large amount of resources to ensure a successful battleground.

Now, that's not to say we aren't willing to put in the time, only that we have an entire game to put resources into, and those resources have to be delegated appropriately. The entire team is now working full force on Wrath of the Lich King, and the new battleground it also includes. Hopefully there will be some time to get additional battleground maps into the mix even after it ships. Personally though I think I'm most excited about Lake Wintergrasp just to see how it turns out.

In any case I'm sure the people you've been playing with have appreciated your time with them in the game, and I think you'll be pretty excited with the stuff going on in Wrath once we get a bit closer and can start revealing more and more. But I hope you had fun, and see you around maybe.

This is a bug fix to prevent clipping of hair through the front of the helmet. We currently do not have the capability to turn off part of an avatar's hair, it's all or nothing and the item designers make a decision on which one is most attractive to the largest number of hairstyles.

If your particular hairstyle does not look appropriate with the helmet then I would suggest turning the helmet off in your options menu.

The QA process for a "universal" or one-step patch is much more involved and time consuming than for an incremental patch from version X to X+1. During PTR where we may revise the build one or two times a week, that extra testing time might add more delay than we would like. There is a trade off here - if it gets really out of hand then we might just advise PTR testers to delete their WoWTest folder and we could release a new step-1 patch.

Vista / WotLK Graphic upgrade
The Expansion is not going to require users to upgrade to Vista. We have some things in the works on the end of graphics, but it's not anything that is going to require this specific upgrade. (Source)

Death Knight unlocking
The thing to keep in mind is that no official information has been provided on how this will work. We don't plan to make it a big hassle as we want everybody to have the option to play the class, but that is all we have stated so far. (Source)

Housing
We also wouldn't want to squeeze in a new feature like this just to have it. Anything we implement has to meet and satisfy our own standards. We have heard the desire for this feature for players, but for now we will have to wait and see as we have no further details on the topic. (Source)