I just learned of this new login authentication service that uses your Bitcoin wallet to login to various places.  Instead of "Connect with Google" or "Connect with Facebook" instead you can "Connect with Bitcoin". 

http://www.coindesk.com/authentication-protocol-bitid-lets-users-connect-bitcoin/

My gut reaction is that this is not a good idea.  It creates another system that needs to access your private key.  Why is that necessary when you aren't making a payment?  For example, if I want to access my hotel room - instead of a key;swipe card;access code - BitID would allow you to use your bitcoin wallet.   But this means the authentication mechanism needs to access my private key.  Why do I want that happening when an access code or something would not put my wallet credentials at more risk?

Thoughts?