Hi. First post
I would have to say that in regards to vocal harmonies, The Zombies deserve a special mention too.
The Who are my favourite band. My favourite albums would have to be Sell Out, Tommy and Who's Next. One album that has not been mentioned too much in this thread is Who are you. Not their greatest album, but a good return to form after the somewhat mediocre By Numbers. It also features my favourite Entwistle composition - Trick of the Light.
For people who are just getting into The Who, I do also recommend a compilation. The Who started off as a singles band and some of their best songs are not on the albums (Substitute, I'm a Boy, The Seeker etc).