USCIS revisions and improvements to Form I-9 include new fields, reformatting to reduce errors, and clearer instructions to both employees and employers. After May 7, 2013, employers must only use this new Form I-9 (Rev. 03/08/13)N.
The new I-9 form can be found online at http://www.uscis.gov/files/form/i-9.pdf.