A master use of the English language, "O_O," definitely not to be confused with "o_O" is a popular emoticon used with instant messaging and Internet Relay Chat (IRC). In fact, ChatZilla, a popular IRC client, even has an emoticon for "O_O," which has been deemed by many "O_O" fans as downright hilarious.
"O_O" is usually used after and between perverted statements, as well as after surprising or shocking statements. Though it may hard to believe, if one is exposed to "O_O," it is usually very hard not to use the emoticon again due to its attractiveness.
<Christina> Potter, may I have the commands if you have them O_O
<Potter> Tell me when you've added one for Lanta Jones. O_O
<Potter> sorry O_O
<Potter> DON'T HATE ME. I'M ONLY 11.
<Potter> jk O_O
<Potter> found it O_O