I received the following to better explain Blogger's decision to support Atom for syndication feeds:
"Hi Steve, I work on the Blogger team here at Google. I just read your latest post on the Blogger Blog, and wanted to give a bit more insight as to why we're making Atom feeds available to all our users.
First, RSS has only ever been available to BloggerPro users, and we've decided to keep providing legacy support for it.
Atom is a unified publishing standard for blogging and syndication inspired in great part by RSS — an early form of syndication that attracted attention and enthusiasm for the way in which it allowed developers and users to share and communicate personal content. However, as RSS grew in popularity developers and specialists realized this early system could not hold up under the stress of emerging demands.
This realization resulted in a massive cooperative effort to create a next generation personal publishing standard that would be 100% vendor neutral, implemented by everybody, freely extensible, and thoroughly specified. Thus, Atom was created. Blogger's commitment to this widely accepted format means that we encourage the use of Atom over RSS. For more information about Atom, you can visit the official web site Atomenabled.org: http://atomenabled.org/.
Let me know if you have any other questions."