I'd say the takeway from yipit is that they need to build a better product. If the engagement is that low after receiving 8k+ hits (resulting in 3 returning users), then it's probably not the right time to work on a marketing strategy. you need to go all the way back and work on the fundamentals of your product. 0.03% (as well as the 1.5% for users who successfully signed up) is an abysmal rate for returning users - no matter how you put it.