Hi Nancy, hi Hismightyness,
@ Nancy: the RSS feed generation has a known issue with displaying entries from child blogs. Some other thread in this forum are discussing it: entries from the parent blog aren't displayed, and this is not the behavior we expect from it. For the moment we do not have an easy workaround: the team is addressing the issue, and you have good chances to see it working correctly in the next version.
@ hismightyness: as far as I know the Blog module RSS feed generation is run hitting directly the database and querying data. This means that all content is shown in the RSS channel immediately after it is added to the database. The problem rises if you use feed readers: Yahoo, for instance, updates the feeds after some hours.
I hope I gave you some help.
Best regards,
Dario Rossa