GM and official iOS 5 = Exact same?

[Spectrum Abuser]

Before anyone says it I know the build orders are the exact same. But my iCloud has ceased to operate and claims that ' There was a problem enabling iCloud Backup.' Tried restoring with the GM IPSW and it did not fix it.

 

[Nermal]

Someone compared the SHA1 checksums, they are bit-for-bit identical.