A newer version of Windows 7 SP1 (Service Pack 1) when comparing with official Windows 7 SP1 RC released by Microsoft has been leaked to Internet. The new build has the version number of 6.1.7601.171257.101210-1930 as v.741, comparing with v.721 for official RC.
Only 32-bit (x86) edition of the Windows 7 SP1 RC Refresh is leaked currently, and the leak is from win7 development branch for wave 1 release, which includes all major 36 core languages of Windows 7, namely Arabic, Bulgarian, Chinese-Hong Kong SAR, Chinese-Simplified, Chinese-Taiwan, Croatian, Czech, Danish, Dutch, English, Estonian, Finnish, French, German, Greek, Hebrew, Hungarian, Italian, Japanese, Korean, Latvian, Lithuanian, Norwegian, Polish, Portuguese-Brazil, Portuguese-Portugal, Romanian, Russian, Serbian, Slovak, Slovenian, Spanish, Swedish, Thai, Turkish, and Ukrainian.
There are rumors that development of SP1 for Windows 7 and Windows Server 2008 R2 has reached RTM milestone, with build string of 7601.17514.101119-1850 (6.1.7601.17514.101119-1850) where EULA states win7sp1_rtm.2_ult_oem_en-us. However, apparently the build may be just a candidate for RTM, with development on SP1 still ongoing. Currently known builds seen on different branches