Why Windows 7 RTM Doesn't Mean Windows 7 Is Done

From Gizmodo -

Windows 7 may be Released to Manufacturing but that doesn't mean it's done. It is still lacking the language packs and OEM builds. The former is obviously needed for other countries (i.e. non-English speaking) and the latter is for manufacturers to bundle the OS with their machines. But if you are one of those English-speaking people who has been using Windows 7 RC without a problem, chances are you can probably use Windows 7 final now and be just fine.