Agree with Ben on #2 - Twitter is far from a being a satisfactory solution for spontaneous group organization. As it has evolved to be increasing about sharing

Agree with Ben on #2 - Twitter is far from a being a satisfactory solution for spontaneous group organization. As it has evolved to be increasing about sharing news, tweets are quick to slip below the fold unless you've limited your following to only your closest friends (and they aren't heavy users). The feed simply isn't conducive to organizing events that are tied to a specific time and only involve a subset of your social network.