How long will the carpet take to dry?

All items cleaned should always dry well within 12 hours.  Every carpet is different, however, and depending on the type of carpet, how dirty things are, and even the outside air temperature can cause things to vary. Air circulation is key to minimizing your dry times! (turning your furnace fan from "AUTO" to "ON" is highly recommended)

Can areas be used while the carpet is still damp?

Absolutely!  By no means are you expected to wait 12 hours to use a room I clean.  It is recommended that if you wear shoes in an area that has been cleaned you first make sure they are nice and clean, and of course your socks may get a little damp if you aren't wearing shoes, but it perfectly safe to walk on.

Do I move furniture?

I will happily move almost all furniture that you request so long as small items and breakables are cleared off the piece in question.  The only items I generally will not move are entertainment centers, large wooden bed frames, and large china cabinets/large hutches.