According to AILA:
“USCIS has informed AILA Liaison that the I-485 form that has been found on the USCIS website with a revision date of 07/30/07N was posted in error. A new I-485 form will be posted on July 30, 2007, but, previous editions of the I-485 form may be used, including the 04/01/06 edition. USCIS is in the process of correcting their website.”