I get the feeling you haven't used IE, hotmail and office for a while. They're definitely not rotting.
"they'll still neglect it until it bit rots enough that a competitor can grab a foothold"
This will not go away, so I wouldn't worry about it.
That IE is no longer rotting is certainly true, but that's only because of the competitive pressure from FF (and now Chrome and Safari as well, of course.)
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With any luck... </post>