This is just a watered down version of the FAQ. The parts that flagger's should be most interested in.
~Things to flag~
promoting things / Chain letters
Threatening the Author. (ex: Go Die!, I am going to kill you, or something similar)
Flooding the review title or body.
long strings of characters or words with no breaks.
repeating words or phrases over and over.
images made from text and characters .
"BLAM this" or something similar
addressing other user's reviews you didn't agree with.
If I missed anything or you think something is not worth flagging please comment and let me know.