I just finished my implementation of the latest draft of the Atom syndication format specification. I am currently publishing an Atom feed written to the new specification. If you use Movable Type you may be interested in my template.
I used permalinks for my id and I realize permalinks are not a permanent identifier throughout time, space, and switching weblog platforms. The id element is changing with each version and I will sit back and watch for best practices before updating my template.