This module builds user profiles as content (aka nodes), which opens the opportunity to use all the powerful modules for content for user profiles too, e.g. the Content Construction Kit (CCK). It's intended to be simple and useful, but extensible by further modules.
Content profiles can be restricted to certain roles; the module also supports separate content profiles for different roles.
Content profile is the successor of the Drupal 5 Node Profile and Bio modules. The intention is to have a common "profiles-as-nodes" base module upon which further extension modules can rely.
Content profile supports upgrading from the 5.x Bio and Node Profile modules.
fago's related blog: link
There is also a related discussion group on groups.drupal.org: profiles-as-nodes
Migration from core profile module: Profile Migrate
Drupal 7: see Profile 2 and #560324: Content profile: Create upgrade path to profile2 and port to Drupal 7.