Ten years ago, you would put out two or three news releases a day for a major event. One in the morning, perhaps an update at mid-day and then something to update the media for the evening news. This is history, given the shift to providing information via social media. The flow can be continuous and the media and your citizens have come to expect this type of immediacy.
Most emergency management agencies have still not cracked the code on "sucking information in" via social media. iI is a perfect way to get better situational awareness. So, don't just push information out — look for tools to such information in — beyond just Tweetdeck.
Brandon Greenberg puts out a weekly tech update at DisasterNet, which is a great source of technology information and where I got my last two blog post links from.