Yup, no login required. :) I used this feature a little bit ago to prepare a computer for my buddy, who wanted to try out one of my Guest Passes - I downloaded and installed the client ahead of time, so when he was ready to try (and create his own account) the game was already done.
So install it on as many computers as you like; it's the user login that makes it all work.
Another aspect to this is you can copy the client across a network. I have downloaded the client one time, and copied it to mulitple computers as it takes 20 minutes or less to copy, and 6 hours or more to download.