Well... I don't claim to be all that good at spelling... but I try. Where I think that it makes a difference - is in either the newspaper, or other media. Another place would be in advertising.
For example, many businesses now have those electronic LED signs, that they can change the wording being scrolled across the sign - with little or no problem. The other day, as I was driving down the freeway, I happened to glance at one sign that was displaying 'comming soon' - or some such. Well... that tells me a lot about the professionalism of the business... they cain't spel. (My mis-spelled words on purpose)
Spell-checkers are only as good as the person using them - most do not catch improper usage of words... I.E.
Mr. Majestic said: ...if people can understand what is being said then that is all that matters surly..??
Well... did he mean 'surly' or 'surely'? They are two different meanings - but a spell-checker would not catch the improper spelling of 'surely' - if that was the word that was meant to be used.
Does it matter? I think so. It shows (to me) the quality of education that an individual has/had. (Note: I did not say LEVEL of education - as I know college-educated people that can't spell worth a darn.)
Of course... there are times, when I will tell a story (through writing) and will purposely mis-spell words. That is equivalent (in my thinking) of talking with an accent.
Regards,
Jim TX