It's day 4 of my 21 days with Twitter. Today, I started using it via the Facebook app, since I hang out there so much, rather than Twitteriffic. It's not as cool looking, but works great. It's also helping to cement my relationship with Facebook, so that's good, too.

I didn't report on days 2 or 3 with Twitter simply because there really wasn't anything to report. I got more random "checking my email" kinds of updates, but nothing worth writing home about (though I suppose we should update that phrase to "nothing worth blogging about"). Today, however, John Edwards Twittered. I mean, he Tweeted. Or did he Twoot? Whatever you call it, what he did was pretty cool. His message:

johnedwards Tell Gonzales, the man who brought us Abu Ghraib, Guantanamo & illegal spying: It's time to go! Sign the petition: http://tinyurl.com/2u945k

Hmmm. He's got 3500 people following him. How many of them took action? Can he measure that? I want to know, what's the ROI on Twitter? In other words, it's awesome that John Edwards is Twittering --  is Barak? Hillary? -- but is it making an impact? Are people discovering him through Twitter? Is he getting people to take action? Are people more informed about him and his positions now? And even if we wanted to, COULD we measure that?

Thoughts please.