I downloaded this ISO and can confirm its hashes match those of the official believed-to-be-RTM:

File Name: 7600.16384.090710-1945_x64fre_client_en-us_Retail_Ultimate-GRMCULXFRER_EN_DVD.iso CRC32: 1ee7dc6f MD5: e6ce9644d0c7a8e1c950d257a7b2c8a4 SHA1: 31849b315290efabfd81f967ed3c553d82925e4c

See:

http://windows7center.com/news/windows-7-rtm-finalized-at-build-7600-download-leaked/

Also, here are the properties of the setup.exe:

http://cid-0edc1d24b4a14025.skydrive.live.com/self.aspx/Public/Signed.png