The above move will increase users faith towards facebook and i am sure that many other social networking sites like twitter, orkut, dig, technorati, Myspace etc. will follow the move and provide their users with security measures in association with IT security firms like Nortron/Avast/Trend Micro/Panda etc.
And this move will definitely improve business and profits of IT Security Firms by reducing their marketing cost and increasing clientele base.