Event Handlers By Design

Interesting article about ItemAdding, and ItemUpdating.

Apparently you cannot get access to the properties.ListItem with the new values to be written , as Microsoft say it's by design.

You must use:

properties.AfterProperties["_INTERNALFIELDNAME_"]

Read more at:

http://www.sharepoint-tips.com/2006/09/synchronous-add-list-event-itemadding.html