You hit on two important points right there. The first is for vendor trash. Who doesn't like vendoring a grey sword and getting a couple gold? Don't po-po that gold, it can add up quickly.
And while RP might not be in your bag of things you enjoy doing, it is for some people -- and Blizzard has made sure there's stuff for them to enjoy.
"How can I find a raiding guild that's efficient yet willing to bring in someone who is just now starting to raid in Wrath?"
You're going to run into two types of guilds. Those who are willing to accept newbies, and those who are not. The key thing you want to do is to keep looking, and don't give up. Look for guilds that advertise they're made of adults and cater to those with jobs, families, etc... They're going to be the most mature people you can find (hopefully). They're also more likely to let you run with them after a few heroics.
If you're looking for a mega-raiding guild that allows in inexperienced people, well, you unfortunately won't find that. The top raiding guilds are at the top because they have very high standards and require serious experience, skill, and gear to get into. Be honest with yourself, right now you don't have that. But in a year? You'll probably have those things if you keep at it.
Baby steps, always baby steps.
"Any information on when race change will be available?"
None yet. The blues answer this question just about every day, and it's always the same. "Soon, but we don't have a date to tell everyone right now." There's already an icon for it in your account admin page, although that's likely there just for marketing and to cut down on the number of mistakenly processed faction changes (people don't read the FAQ where it says the faction transfer is not a racial transfer). My guess is that we'll see it before the end of the year.
"Do most raid groups use 2 or 3 healers in ToC 10 man?"
It varies. If the two healers are really strong either in gear and/or skill, then they can probably do it. If they're lacking in skill and/or gear, they probably will need a third. Of course there are a lot of other factors as well -- tank gear, DPS skill, etc... Whatever works for your raid works, don't worry about it if you're getting the kill. I've ran ToC 10 with as many as 4 healers on a particularly poor healing night.
"Why have they not increased the size of some doorways in Ironforge in-order to accommodate the larger mounts?"
Why do you want to be on your mount inside Ironforge? I don't think the dwarves appreciate that.
Besides dwarven anger, redesigning an entire city's doorways is a major major task, one that their resources probably could be put to better use on.
"I heard a rumour that the guild levelling system was going to be included in patch 3.3. Am I going mad?"
Yes, you are. There is no indication it will be introduced in patch 3.3. It will likely be introduced in patch 4.0/4.02, which will be the huge Cataclysm patch.
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