Yes, they can.
At least that's what the new Blog It application on Facebook is supposed to do. This post is being written from within Facebook, and then should be sent out Real Agent Blogs, Twitter and my FB mini feed.
This could be a handy app if you're using multiple services - also works with other blog platforms like Wordpress, Blogger, Tumblr, Movable Type, Vox and Live Journal.
For the micro crowd, Twitter and Pownce can get the mass update.
This is kind of like spamming yourself.
More info at: http://blogit.typepad.com
Get the app here: http://www.facebook.com/apps/application.php?id=14103720714