RePEc (Research Papers in Economics) just posted that their bibliographic database of working papers, journal articles, books, books chapters and software components has passed two million indexed items including 1,400,000 items indexed with an abstract.
In addition to the milestone RePEc recently launched a new directory of economists using Twitter.
From a Blog Post:
It appears that economists recently have been warming up to the idea, and many prominent ones have joined Twitter and contribute thoughts on policy and current research. The difference with blogs is that Twitter somehow engages more discussion, and it also prompts interactions between people who would never have interacted otherwise: it makes everyone accessible. That said, one can also simply be lurking without intervening and learn from the discussion or the alerts. As we find from analyzing traffic to RePEc, Twitter can drive substantial readership to some papers.
Direct to RePEc Economists on Twitter
EconAcademics is a website that aggregates the discussion of economic research while monitoring about 1000 blogs.