75e85bf1_ter_Go_Mainstream__The_Debate___Con
[0] Eric Berlin [Pro] It is intuitive enough that "civilians" can hit the homepage, register, post their first post and add a few friends within a minute. They can also quickly "get it" and see benefits. It is on the fringes of mainstream exposure with CNN, mentions on the Daily Show, Barack Obama and other non-web celebrities. [Con] 
The combination of other services (Facebook, FriendFeed, Yammer, and new ones not quite on radar yet) will steal Twitter's remarkable thunder and leave it behind.
louisgray.com: Will Twitter Go Mainstream? The Debate.
Con