The title makes a dubious connection between their valuation and their technology. I guess that Secret investors are not interested in the technology but rather the network of users.
I guess it just points out that technology != valuation. However, it also highlights that what Secret is doing isn't terribly special (nor Twitter, etc) and that they have a pretty reasonable chance of someone swooping in and taking over their market (happened with MySpace for example) at some point if the community becomes bored.
Sorry for that! I just wanted to show the connection to a quite recent event, and I actually thought that anybody who knows about Secret already knew that their value is not 100% in their technology.