My guess is that the real reason for this is that Windows 8 will add a native spellcheck API (technically Vista already did, as part of WPF, but that generally isn't used by consumer applications for various reasons), and in the meantime to avoid future confusion they don't want to implement it separately in IE.
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My guess is that the real reason for this is that Windows 8 will add a native spellcheck API (technically Vista already did, as part of WPF, but that generally isn't used by consumer applications for various reasons), and in the meantime to avoid future confusion they don't want to implement it separately in IE.