This is a question that every product manager must answer. Why would your customer take the time to use your product? Why yours? Why not what they already use?
Squidoo is an interesting offering. You can build web pages around any knol you choose. I tried it. I built one for Purdue football. And I put some content on it. And I checked the traffic. Wow, I get more traffic to my personal blog than I do to my Squidoo page (which is zero). Which begs the question: why would I put time into building a Squidoo page? Especially when blogs are easier to build/maintain than a Squidoo page?