*chuckles*
Ya know, I've been known to do that to people...
Okay, first off, CRPG stands for Computer Role-Playing Game. Just like a regular RPG (such as D&D or GURPS), but it's computerized. WW, DD, MM, YY... they're all CRPGs.
IMO is an abbreviation for In My Opinion. You'll see variations like IMHO (IM Humble O) and IMNSHO (IM Not So HO). Other common abbreviations include ROTFL (Rolling on the floor laughing), LMAO (laughing my @$$ off), ROTFLMAO (doing both)... there are a billion of 'em.
Check out
http://www.geocities.com/SouthBeach/...#Abbreviations for a listing and a link to a larger dictionary.