My first-hand lesson about how social media messages depend on content and relevance, posted on 11 January, reminded me of a successful client we worked with in the late 1990s.
This client had his own formula for marketing: Message, Media, Creative. The idea was to start by figuring out what you wanted to say (Message), where is the place to say it (Media), and how to say it in a way memorable, convincing, and relevant to the medium (Creative).
This formula works as well today as it did way back in the 20th Century. The greatest channel-neutral plan or the most entertaining creative don't mean bubkes if the message isn't appealing.
A modern example of this principle is the above Google diagram* describing how your SEM copy is everything when inviting consumers to your cause. It's actual advice is: "A successful link bait can increase inbound links, traffic and brand awareness."
In English: If you have a strong message, suitable for SEM and write it well, you can meet your objective.
* Hat tip: the blogress Little Miss Jen.