I think it is safe to assume you are a more mature person but even though you really do need to grow up.
Yes there is some very hateful posts made about Howard, but there are also similar posts made about Rudd.
Why is it you are not whining about those posts as well.
People will always Hate as you put it polical leaders,sometime for no other reason than the side of politics they are from and some times because of the things they have done.
You clearly thing Howard has done a good job, you are entitled to your opinion but he could have ordered the nuking of Melbourne and Sydney and you would still support him.
But there are also those who do not think Howard has done such a great job and in some areas has made a complete mess of things and some even dislike or even hate him for what he has done (eg joining a war that we should have had no part in) this people are also entitled to their views and to express them.