I hate that people feel that it's ok to have incorrect spelling and grammar if they are writing on the Internet! My sister is particularly guilty of this, but I run into it everywhere - including places that should know better. Now, I know that I don't have perfect grammar ALL the time, and there are many occasions where my spell check catches a few words. Typing quickly, or being in a rush, can often lead to spelling and grammar mistakes. But seriously, people? Get with it. Because someday, your lack of grammar skills is going to catch up for you.
Biggest offender:
"I" instead of "me" when describing a photo. Ex: "This is Sarah and I at the zoo." NO. It's "Sarah and ME." You wouldn't say "This is I at the zoo," so what drives you to write "I"???
1st runner up:
"Your" instead of "you're." Ex: "Your beautiful." Your beautiful what?? It's YOU ARE beautiful! Get it right!
2nd runner up:
"There," "their," and "they're." Suggestion: Take the extra two seconds it takes to make sure you're using the correct version, so that you don't look like a complete and moronic asshole.
I shake my fist at bad grammar!