It is very important to remember anything you say on the net is out there for anybody and everybody. You never know who is reading you blog - even with trackbacks that give you some stats - you don't know who the people are and even if you delete it 5 minutes after you have posted it there's a chance that SOMEONE read it...
Also, you need to be aware of the way in which your words may be perceived. In my experience sarcasm does not work too well in the virtual world. There are no facial clues, no inflections/tones in the voice, no body language... Words may be interpreted in many ways.
Just something to keep in mind...
Part of my code/way of life/whatever is to:
1. Practice common sense
2. Be aware of my surroundings
Number 1 translates to every aspect of my life.
Number 2 does too... maybe for the blogosphere surroundings could be replaced with audience...