My small site went up nicely in the update. Most of the formerly PR 0 and 2 pages went up to PR 3, including the home page. But curiously, one of my inner pages got a PR 4, thus outranking the PR 3 of the home page. Is this unusual? I suspect(?) that the reason is this: I singled out that one page (http://www.jimfeeney.org/pro-life.html) and submitted it laboriously, one at a time, to about 100 pro-life websites. From that effort about a dozen of those sites linked back to that page. Maybe I've answered my question (i.e., those new backlinks), unless you can think of some other reason for an inner page to outrank the home page.
PR is assigned on a page level. It's not unusual for inner pages to have higher PR than the index if you do some deep linking.
It is the page that gets "page"rank not the site/domain so your homepage does not always have to have the higher rank, it just usually works out that way with linking but if you have good internal links then it would be quite normal.
I'm seeing the same thing. My main page stayed at PR3 but my sitemap went to 4. No one links to my sitemap, in fact before it had pr0. Explain that...