If you’re using http://spaces.msn.com and wonder how people are updating their spaces via e-mail, it’s not that difficult – the information is just buried.
From you spaces home, click on Settings then Mobile Settings. You have to turn on mobile publishing, identify the “from” e-mail address from which your e-mail posts will be sent, provide a secret word (more on that in a bit), then tell the system if you want the posts to be saved as drafts or published immediately. (The secret word that you provide is appended to your spaces name, such as email@example.com.)
Just send an e-mail from the account you specified to the firstname.lastname@example.org e-mail address.