When doing an export to CSV data, dates are formatted MM/DD/YY, and even in the civicrm_generated sample, some of the dates appear to be ambiguous as to century.
Default format for en_US locale probably should be MM/DD/YYYY instead.
0) Using CRM 1.4 alpha, PHP5 version under Drupal 4.7:
1) Go to Advanced Search, and select all contacts.
2) Choose "Export Contacts" and click "Go"
3) Choose "Export PRIMARY fields" (bonus issue: it says "exporting 1 contact". Ain't true)
4) The download will start and will work fine. But the dates are formatted MM/DD/YY.