Let's say for the sake of argument I prefer to vote Wombat (or some other minority party that doesn't stand a cat's chance in hell of winning the seat here).
With FPTP, my vote is pointless, they can't win, so I don't bother.
With AV, I can vote Wombat but then say my second-preference is the Duck-Billed Platypus candidate who actually stands a chance of winning. I can vote for my preferred party, but also have a vote that counts, so I do vote.
I think that anything that encourages people to get out and vote is a good thing.
Oh yeah - politicians say different things to difference people now already, so that won't change...