You will be so what? Frustrated? Wrong! You won't care because all you need to do is start it up again and click "Recover post." Blogger now auto-saves as you type. (We just launched this feature today so you may need to reload you new post window to see it.)
Update: Blogger Help article on recover post.
Update#2: We noticed a bug in the wee hours of the night that could annoy some users so we've temporarilly disabled the recover post feature. We're fixing it now.
Update#3: Recover Post is back and better than ever!
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