In terms of engaging citizen, I think that what is crucial is to find attractive and convenient ways for citizens to spend time understanding the challenges threatening their community.
That's what town hall meetings do. Town hall meetings are informal public meeting open to everybody in a town community with attendees discussing the issues of the community.
The problem with town hall meetings is that participants need to be physically present under the same roof which restricts its use to small towns.
The way for tech to disrupt politics from an engagement perspective is to leverage the Internet to mimic town hall meetings with hundreds of citizens having simultaneously dozens of conversations on community issues.
Using the Internet and webcams, virtual town hall meetings free participants from the physical presence limitation.
-Check virtual-hub.org for a virtual town hall meeting application used for the Nov. 8th election in Berkeley.