I agree with william though. With my failing eyesight and general predisposition to laziness, I thought it would be nice, and it seems to be an agreeable feature as Ron and others (and I agree) have stated emphatically that words spelled incorrectly are a great distraction.
Then there are just some words that are misspelled so often many don't even realizing they are not spelled correctly. (I am thinking of devine for divine, and I also have problems with seperate, etc.)
And sure, I can and do proofread, and edit, but I figure a place that has word filters could incorporate a little convenient feature, available at most other sites.
But it ain't some huge thing for me, and I ain't up for six more years of annoying poor Ron, so, laughing...I exit with a shrug.