It's not just spelling (we all make the odd mistake now and again) but the total lack of grammar in some posts just blows me away. The use of the wrong homonym (their, there, they're, to, too, and two are six examples), capitalization and puctuation, improper sentence and paragraph structure just kill me, particularly when the post turns into one long paragraph.
If you are going to all the trouble of typing a long post, which you hope someone is going to read and possibly comment on, why wouldn't you try to make it as readable as possible?
Sometimes with the one line posts on here you would think the individual has one of the TERB for Blackberry or iPhone applications the way they punch it out like a 140 character text message or twitter update. BTW, when does Fred have those mini-apps coming out? I really want to be there when some guy's wife or girlfriend picks up his smartphone and says "What's this TERB honey?"