With all of our social media outreach, we at Gerris work on providing earned media for our clients. It is important to decide where you want to spend your limited resources. Do you want to spend it on contextual ads? Contextual ads can drive a lot of traffic immediately to your target, to be sure, but when you stop paying for your key words, everything comes to a halt. All that traffic goes away... and, even while you're paying for the ads, the conversion might not be there -- it might just be a waste of money, a budget burn.
When you put your time and budget into blogger outreach, social media outreach, and blogging, your results may be less immediate than they are with ads, but whatever coverage you get, whatever earned media -- and it can be an astounding amount of coverage, too -- never goes away.Never! It becomes permanent record on the Interwebs, stashed and findable on Google until the Internet collapses through some sort of evil DNS hack.