>>>>Prolly the dudes running stormbot.
>>>>
>>>>>http://www.foxnews.com/politics/2008/11/20/pentagon-cyber-siege-unprecedented-attack/
>>>
>>>What's "prolly"?
>>
>>Probably.
>
>OIC. Is this a common US abbrev. for that?

Not widely used but common enough to be recognized. I don't think I have ever heard anyone say it that way, it's more of a chat tic.