I think it varies from area to area. We have a couple Tau players here but no orks really. Couple eldar and a lot of space marines. I've played a LOT of matches and have yet to play against orks.
Exactly, if people would look around before posting these things they would see it has been answered, they would also see that a lot of people want Tau we understand however, they will not be in at launch.
I want them in, but trying to balance a game that heavily emphasises melee combat around a race that is entirely focused around being annoying as possible at range and staying out of your range is a nightmare.
Because Tau are one of the smaller factions and are only located around a very small part of the galaxy.
We don't have Tau because if we did we would all want Crisis Suits and that's just beardy plus all the other races would whine about a longer range jumpier armor and shootier guns. Tau are one of my favorite table top armies.