Nielsen, in trying to get at Twitter's impact, compares its Web traffic to that of MySpace and Facebook, and retention of users at a similar stage in each company on their websites. But, today, making someone go to a specific site can in itself be considered a weakness -- a lesson Facebook appears to be learning with Facebook Connect and more open architecture that allows people to interact, at least some, "off-deck."
Each of these social networks is different, impactful in different ways. I discover musicians on MySpace, friends and colleagues on Facebook, colleagues and business leads on LinkedIn and news on Twitter. Each feels different, and attracts different crowds and different uses. As Twitter is unique in its use case, stats that count only its website's traffic don't just miss the boat quantitatively, but there's also a qualitative disconnect.
I hope to explore this topic with Jon Gibs of Nielsen, when he's on Naked Media next month, along with Todd Juenger of TiVo.
An aside: It's incredibly frustrating that I have to go to a Facebook, or LinkedIn or any other page to communicate w/ my network(s), rather than being able to easily have it all in one place. (I am aware of one venture trying to let folks do it all through one interface -- I hope they get funding and come out of the box strong. And I hope their architecture is open.)