http://www.webopedia.com/quick_ref/textmessageabbreviations.asp#M

is a useful online guide to such standard web abbreviations. Many, such as lol ['laugh out loud' or 'lots of love'], btw ['by the way'], 2MI ['too much information'] have got out and become mainstream, so you will find journos using them in features and expecting to be understood. They can, iirc ['if I remember correctly'] and SFAICS ['so far as I can see'] be typed in upper or lower case.

HTH ['hope this helps']

~M~