I actually think Microsoft wants firefox/opera/other browsers to over take it.
Now web browsers have just become a part of daily computing life, and most people expect browsers to be free (Legal copies of opera will be for the true elite, like me
) there is not much money to be made from creating a killer web browser, Windows Media gets money from licensing content and MSN Music etc..., but there is not much scope for making money in a web browser.
So, the more people that use alternate browser, the less attention IE and its flaws get, that means Microsoft can shift coders from working on IE, to working on other projects that can pull in more money, sure they can release the occasional update to keep the IE users happy, but apart from that they can stop major work on IE.
Just an opinion
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