the best way to increase the signal to noise ratio is to install a third party filter program. FB Purity, is an excellent example, it filters out all the previously mentioned application spam, and also lets you filter out events, facebook places, tagged in messages, etc etc. You can hide as many message types as you like, you will notice a huge improvement, you can get it here: http://www.fbpurity.com
the more features they add to facebook, the more noise it seems to generate, and the more the signal gets lost. the problem is the noise is put there by facebook to try and keep people glued to the site, because the more updates you need to chew through before you get to the interesting content the more time you spend on the site, and the more time you spend on the site, the more dollars they can get for advertising. anyway the only way to get rid of all the noise is to use third party filtering, my weapon of choice is FB Purity its a browser extension available for all the major browsers it gives you options to filter out the noiser functions and components of Facebook, and also gives you a word or phrase filter, so you can specify the textual content that you wish to hide from the steram. Its a great add-on, highly recommended for people that want to tame their noisy news feeds: You can get it here: http://www.fbpurity.com
another great extension for improving sanity and privacy on facebook is f.b purity. The app blocking functionality, helps protect your privacy from all those spammy quiz and game applications that appear in your newsfeed http://www.fbpurity.com