Without support for in text spell checking and the need to click a button and enter a spell checking mode IE 8 failes for me on a critical test.
I won't be using it anymore. Microsoft this was such a simple thing, how could you get it wrong. Firefox has done this for years, and that is where I will be going.
I have gotten so use to everything from my iPhone to my Word to my Flock browser correcting my spelling in real time I simply can't believe Microsoft, who have the most experience of all in doing this, overlooked putting it in their browser.