• Extraction of data from other databases and files, including SQL, CSV, XML, DBM, etc;
• Accented & international character set handling and correction, e.g. ISO8859, utf8, CP1252, Unicode, HTML entities and combinations of these; (typical problems where content has been entered by "cut and paste")
• Data import into Drupal via XML-RPC, including handling of comments with correct date setting;
• Data manipulation, e.g. substitutions, field splitting/merging, etc.
• Data validation, e.g. RFC-822 email address conformance, URL/URI checking, etc;
• Addition of Taxonomy terms to imported content.

If what you need to do is beyond the capabilities of the Node Import module, maybe these will be of help you.

Andy