The White House famously switched its site to Drupal last year, following its initial use at Recovery.gov. A Community Management Service package like Drupal makes great sense for any organization that updates its site a lot, and that wants to empower managers to do their own updating.
I wrote several years ago that Howard Dean might have become President had he switched to a scaled CMS. Instead he stayed with Movable Type and failed to scale the intimacy of his early run. I even offered detailed advice on this at my personal blog. Someone was listening because the Obama campaign made heavy use of scaled CMS tools, not just blog platforms.
Even more important, I think, is the hiring of Tim Bertrand as a vice president of business development, and bringing in Carahsoft as a reseller. If you want to sell to government, get someone with government selling experience. This will even help in Gullyvornia.
I don't know whether this will make Drupal a standard for government Web sites, but it does steal a march on rivals like WordPress' Automattic. (Of course, Automattic still has cooler corporate titles. ZDNet runs on Wordpress.)