Blogs are passe. Tweeting on twitter.com is now mainstream and the geoscience community is embracing it. [this sentence took 85 characters, well within the twitter limit of 140, so I could have tweeted it]
I'm following four twitter feeds, albeit intermittently:
Each of these is serving primarily as an aggregator of geo-news from a wide array of sources. With RSS feeds, these sit on the tool bar above my browser. A quick click, and I see instantaneous lists of what's happening in the world of geoscience. Many of the tweets are links to blog posts or news headlines. Some report geologic events as they are unfolding.