Pros
You get your own blog and you will have full control over it.
You are free to create any type of blog you choose.
There are many themes to choose from for your blog.
You can try TypePad for free before deciding if you want to purchase an account.
You can use your own ads on your blog.
They offer a spam fighting service.
You can edit the HTML if you need too.
JavaScript is Allowed.
Cons
You have to pay so much a month to use the blog and there are so many available that are free.
The technical help sometimes takes a while to get back to you.
The business blogs are almost $100 a month.