Update 2007-11-21: FeedWordPress 0.981 is now out of date. You can download the latest release — 0.991 at the time of this writing — from the project homepage.
If you have been experiencing a bug with FeedWordPress 0.981, which leads to new posts from Atom feeds being dated back to 1970, then you should download a fresh copy of FWP 0.981. Some user bug reports (thanks!) alerted me to the fact that I’d accidentally packaged an older version of the MagpieRSS upgrade in the 0.981 release, which did not fix this bug. The correct version of `rss.php` is now included, and will solve the problem.
You can get the fix by grabbing 0.981 in a gzipped tar(http://projects.radgeek.com/download/feedwordpress-0.981.tar.gz) or 0.981 in a zip archive(http://projects.radgeek.com/download/feedwordpress-0.981.zip).