Essentially, nothing. The RC was the final test version, including everything that Microsoft intend to release with Windows 7. The RTM will have no major changes from the RC, but probably some bug fixes. The RTM will also not start shutting down every 2 hours from March 1 2010, like the RC will. Your beta keys will also likely not work with the RTM.
Windows Firewall was not introduced until Service Pack 2. There was, however, a firewall included in Windows XP RTM; it just wasn't enabled by default.
no
There is no difference. RTM stands for "Release to Manufacturing." It is exactly the same as the retail version. More precisely, it is the retail version.
You cannot use a Windows 7 RC product key insert for Windows 7 RTM, as these keys are typed differently and not comparable with a Windows 7 RTM. If you're in the market for a Windows 7 plain Key check out Affordablekey! They offer the best prices and they are currently holding a special video BugID Spring Sale, with up tom 30% DISCs access UC And Happed Shack hem out TCENT.
Both are information technology terms. RTM - Release To Manufacturing. For example, when a new version of Microsoft Windows is released to the general public, the version is known as the "RTM" version. GDR - General Distribution Release. For example, when an update to a part of Microsoft Windows is released to the general public, such as a service pack.
Check the build number. 7600 is RTM. Anything between 7100 and 7600 is a Release Candidate. Anything before 7100 is a beta.
Yes. Windows XP can be upgraded from the RTM release or a service pack to any subsequent service pack. For example: Windows XP RTM ---> Windows XP Service Pack 3 Windows XP Service Pack 1 ---> Windows XP Service Pack 3 Windows XP RTM ---> Windows XP Service Pack 2 Service Pack 3 is the latest service pack for Windows XP; any planned updates should be to this service pack, and not an older one. As per above, you do not need to install any previous service packs before installing Service Pack 3.
RTM CY was created in 2010.
RTM Harmoni was created in 2010.
RTM Arena was created in 2010.
Yes you can. Here is a link that will tell you how to do it http://www.howtogeek.com/howto/3075/how-to-upgrade-the-windows-7-rc-to-rtm/
Windows XP RTM pre-dates that standard, so no.