It's not continuous. Once you block an application (e.g. the ubiquitous Farmville), you will never see an update from Farmville again - easy peasy.t's easier delete them as friends rather than continously blocking the game/group application messages.
When you mouseover the message, a 'hide' button appears to the right. Just click it.If you could block messages like "XYZ became a fan of having a cup of tea in the morning" then Facebook (and my life) would be a damn sight better.
It's not continuous. Once you block an application (e.g. the ubiquitous Farmville), you will never see an update from Farmville again - easy peasy.