I've always liked spelling and writing, and when I was a kid I was one of the best spellers in my class. Now, in my professional as well as my personal life, I've discovered how important it is to be able to spell correctly.
When I read other people's writings, and even more, when I see companies' presentations, brochures etc, I've noted how much a misspelled word affects my impression of it. One typo: fine, shit happens. Lots of typos: a sloppy and rushed impression. And when I read things what web developers have written, if it's littered with typos, I definitely think twice before I want them to write any code for me.
When I became friends with Faruk, I immediately realized how good he was at spotting typos in my posts. Naturally, my reaction was part gratefulness, part me in turn scrutinizing his posts to find errors (and man, was that hard! :-)). In the end, though, I really do appreciate when people notify me when I have typos in my text, so if you see anything, please let me know.
And remember: it's our language that differs us from apes. ;-)