This could be very helpful, so long as academics maintain their profiles. I currently use an ad-hoc system of Google Reader's "check if webpage changed" functionality to check for new papers in my fields of interest. For economics, these are listed on pages like:

http://papers.ssrn.com/sol3/JELJOUR_Results.cfm?code=M13

http://papers.ssrn.com/sol3/JELJOUR_Results.cfm?code=G24

which gives an ugly summary of updates to non-RSS friendly websites. Academia.edu appears to require that

1. Authors sign up

2. Authors also update their profiles with their new research

My experience suggests this will be difficult for econ: I repeated the Google readers process for the active authors in my field. Google tracks their "Working Papers" pages for updates and lets me know when they add a paper (or change a font!) For the two dozen authors I track, only one has updated their page in the last two months.

And we're hiring: http://www.academia.edu/jobs

We're based in downtown SF and we're looking for engineers to help us build a great product for researchers.

They have Hawking, Dawkins, Chomsky, Krugman on board already as scientists. Wow.

I just signed up, and the web site is remarkably slick. Anybody who's made web apps knows how hard it is to make something that just does what it's supposed to as well as this. I especially like the easy integration with GMail, Facebook, and so on.

The signup process is a bit long, but I'm not sure if that's a bad thing.

Edit: When I selected "Electrical & Computer Engineering" from the drop-down menu of departments, the ampersand got turned into "&". I'm pretty sure this is a bug.

Excuse my ignorance, but how did they get a .edu?

How did they manage to get the domain name? From http://en.wikipedia.org/wiki/.edu:

Starting on October 29, 2001, only post-secondary institutions and organizations that are accredited by an agency on the U.S. Department of Education's list of nationally recognized accrediting agencies are eligible to apply for a edu domain.