How four social networks inform me about the current Israel/Gaza conflict, in order of where I first started seeing things:
Facebook: Shares of pro-Israel/anti-Gaza graphics, some of them direct Israeli Defense Force propaganda with the identifying logo at the bottom. All of the sharers are personally known to me, and all are Jewish. Most (maybe all?) of the shares are made without comment, as if the graphic itself says everything the person posting it feels necessary to say.
Twitter: Tweets from a number of users, all left-leaning, who link or retweet longer, thoughtful articles examining various aspects of the conflict. Many of the articles are meta-commentary about media coverage of the conflict.
LiveJournal: A single user (osewalrus), well-informed, who personally favors Israel, but offers up commentary and advice that takes the motives and goals of both sides seriously. And one other guy who made a passing reference while talking about something else.
Google+: Nothing yet. Right now, the only post I see on my G+ stream that mentions Israel does so in the context of criticizing American airport security.
This confirms reinforces for me a number of beliefs I already held about the services (no doubt shaped by my particular use of those networks, and thus possibly not truly representative):
Facebook is for shallow, unreflective contact. (Also: Most of my relatives and some of my friends are reflexive and thoughtless in their support of Israel.)
Twitter is mostly tech-savvy and intellectual.
LiveJournal is pretty much dying off, unless you speak Russian. Also, osewalrus is a pretty smart guy.
Google+ is great for talking about role-playing games, not for much of anything else.