I really love this infographic from vocus.com. It summarizes the industry so well, and what small-to-large businesses ought to be focusing their marketing efforts on these days.
One of my first takeaways from this infographic is that a business that is in the early stages of introducing itself to its market should focus on marketing efforts that require less attention from its audience, and, as the business grows in notoriety, it will have a chance to benefit from other, powerful marketing methods with its larger garnered attention.
Not all of these methods will be for everyone, and this infographic does a great job of explaining the value and difficulty of each. Depending on the skills and resources at hand for a business, some methods are going to be natural choices above others. [+]