Yesterday White House, GSA, and OMB released the official list of .gov domains
1,759 is obviously a ton of domains and lots can be consolidated.
I do have to say that you count them in a bunch of different ways as lot of domains redirect to others like hotels.gov that redirects to a GSA.gov page on Fedrooms - http://www.gsa.gov/portal/content/104419
Or Consumer Finance Bureau has:
Some could argue those should count differently. It would be interesting to see the number of domains a similar sized company owns (for example, a GE or Coca-Cola) as I'm guessing it's a number.
I'd also like to see the number of domains that are actually hosting websites VS re-directing.