Does anyone use Sidewiki?

Some weeks ago, I noted the existence of Google's Sidewiki (Is Sidewiki evil? (Probably not, but it's annoying)) and mentioned that I'd planned to install a Sidewiki blocker on my websites.  Well, I've done that.  I've also installed the Google Toolbar thing, and now have a Sidewiki button nestled up there next to my Firefox URL box.

Every so often, I click on it to see if a website has any Sidewiki annotation, but thus far, I've yet to see one.  Does this mean that Sidewiki's a flop?  Or just reflect the nature of the sites I visit (many are forums or blogs with pages of relatively transient interest)?  And need I have bothered to install a Sidewiki blocker at all?