There is a very good comment on the post explaining the difference between Marketing, Public Relation, Advertising and Branding. The comment is from a guy called Tricky and explains other forms of interaction between companies and consumers like Tech Support, Direct Marketing, Telemarketing, … I reproduced it below: 

The buzz word in today’s business world is [...]

Ads of the world published a funny set of pictures that explain the difference between Marketing, Public Relation, Advertising and Branding:

Image courtesy of Neutron, LLC.

Another example of ubiquitous blog usage is shown by Marc Andreessen which uses his blog to post job posting.

Mashable published a handy list of tools for LinkedIn. Those tools are mainly plugins or widgets to grab your LinkedIn profile and display it on your blog or on Facebook.