Will others know the name I’m bidding on during the 3 day bid period?

The names are not publicised, however, the fingerprint (hash) of the name is published as soon as the auction is started. If you are bidding on a dictionary word or a name that is in top 1 million DNS Domains list, the name you are bidding on can be easily guessed. However, the amount you are bidding is still a secret.
ENS Auction Bot (https://twitter.com/EnsBot) tweets anytime a bid is started for a well-known name.

Tags: .eth, Ethereum