One thing that's been true about the internet since its inception is that its quality of writing is pretty poor.  I'm not talking about the content or the way it's written, but about the spelling and grammar.  And this website is no exception.  I've stated before that I sort of employ my own interpretation of accepted grammar rules.  This is another way of saying "I don't use proper grammar when I write."  Spelling, on the other hand, is usually an automatic thing:  There are plugins and web browsers that automatically point out mistakes, so it'd be stupid to not use them. 

The errors I see most often are twofold:  (1) Confusion with there/their/they're and other similar words, and (2) sentences that don't make sense because they're missing words or don't have a matching subject and verb.  Concerning this site, I make no claims as to the perfection of spelling, grammar, or anything else, mainly because I'm one person.  I do this in my free time.  I don't have an editor.  I proofread things before I publish them, but my eyes don't always catch everything.  But with bigger sites, this really shouldn't be a problem.  If you have an editor and there are still spelling and grammar mistakes, fire your editor.  Mid-sized sites (with editors) like TechCrunch shouldn't be publishing sentences like this: 
Keyhole provided Google Earth, a downloadable program that gave a then unprecedented view of the earth through the use of satellite imagery, but Google isn't a software company, Picasa and a few small efforts aside.
Bigger sites like Yahoo and CNN are usually pretty good about either having several people proofread or just having very careful and smart people in the first place.  But I still occasionally notice little spelling and grammar mistakes, and it annoys me.  Proofread before you publish! 

[Note:  This post probably has spelling and grammar mistakes.] #language