Of course I don't agree but I do accept some of Paul's points. I agree that the time when you could "become famous" through blogging is probably over. If that is your motivation then you should probably pass over blogging and get with the next big thing be it twitter or face book or more likely something else that most of us haven't even heard of yet.
On the other hand there are many other reasons to keep a blog. It can be a personal creative outlet. It can be your very own soap box. You can use it as a kind of online diary. It can add a new dimension to your hobbies. It can be a social thing. You may be even be lucky enough to find a community of like minded bloggers.
Telling people to stop blogging because they have no chance of getting to the front page of Google is like telling amateur musicians not to bother because they have no chance of getting to Carnegie Hall.