Blogging, I would say, is a double-edged sword.
As you may have heard once or a number of times, the pen is mightier than the sword. Words have a special way of changing someone's life-- for better and for worse. As much as it can inspire someone to change into someone much better, it is also capable crippling the human being, leaving him scarred forever or perhaps incapacitated to do something which he had previously so freely and capably enjoyed. The written word--unlike the spoken word which may more likely require the constant transmission from one person to another to stay "alive"-- can be always brought to life in its original form so long as the medium exists.
With the advent of blogging, making yourself heard by millions of people who have access to the net has become possible. And all you might need is internet access, your material and of course your blog site. It's become so simple to write down those thoughts that blogging has even taken a very personal and subjective dimension-- much simpler than having to wait for an editor to read through your work and approve of having it published! With such simplicity then, the writing and publishing process is prone to becoming an act of little thought or oftentimes of no thought at all. And of course, when I mean of no thought, this refers to consideration of errors in one's writing, the content of what he has written and the impact it would make and his sense of responsibility to account for what he has said in the event that he would be asked to defend them. Hence, this is the reason and need for "blog ethics".
Just as other written works, meant to be read by the public, have their ethical laws which ought to protect people from "stabbing" each other with little thought through wrongly-chosen words... so should it follow that blogging be done responsibly.
But of course, who am I to say that adding the personal touch to your personal blog ought to be curtailed? That would be like losing the purpose of having a blog in the first place, wouldn't it? How could anyone demand ethics when it just so happens that you believe that a blog should be a medium to draw out your very strong feelings about a particular issue? Or better yet, that you believe that true writing is to be able to write with passion, undistilled, pure and in its "raw form".
And this is where blogging becomes a double-edged sword. Just as you believe that your blog is a personal page to express who you are, keep in mind that just about anyone can also have access to these very personal thoughts of yours. And there is nothing wrong about having to express your opinion on a topic, but at the very least be considerate enough to provide reasons for your statements and to think of people who would be reading your work.
What fun is it to read a blog that just throws around words, expressing this whirlwind of emotion without even any explanation or justification to be such? As a writer, it may feel wonderful that no one but you can understand what you're trying to express in your elusive and stylish use of metaphors and figures of speech; it may feel so "superior" to actually be understood by the few who think they've understood what you mean and have praised you for being able to say such things. But a true writer not only aspires to express rather than impress, but he seeks ways to improve his craft and makes his work with much thought.
And of course, as I'm talking about "ethics", it must also be mentioned that blogging should not be a means for anyone to begin nor to end a fight which is better off discussed in private among only those concerned.
Yes, no one can tell you what to write. The whole cyberspace and your bandwidth are your limits for writing down your thoughts. But at the same time, please think of your readers. Those erroneous ideas may actually inspire someone who knows no better, and he may even believe in them. As a writer, you may not be responsible for a person's beliefs, but you are responsible for inducing them to believe in it (if you did contribute to that.)... and you are responsible for what you speak and what you write. As soon as those words go into the public domain, you are accountable for them.
Though at first it may seem pointless and time-consuming to actually edit your work before publishing it for others to see, such attention will undeniably not go unnoticed. And for sure, while you spare yourself from a potential future of shame, your writing skills might even improve as you progress.