on Aggramar we used to have at least 8 multiboxers, but the majority left for PVP servers. i know of a couple of people that are looking to start Multiboxong on the server so we would be looking to run 10 mans initally and who know at a later date (maybe 25 man content).

I currently have 6 teams of 5 ranging from 60 to 70 and spend a couple of days in on each with frequient rotation, to get them all up to 70
the server community as a whole is quite tolerant of Multiboxers, I find it's rare to get any negative comments. (you occasionally get some negative comments, but that's the same on each server).

As for your AH inquiry, the place is quite well stocked and stuff has quite a high turn around.