I have been using the beta of Windows Live Writer for over a month and I can now say that without a doubt, it has totally changed my blogging experience.

Live Writer plugs seamlessly into the WordPress blogging engine I use.  Since I'm using a Windows application, I find that amount of time it takes to create a blog post has been cut down by at least half.  It also makes things like inserting pictures into a post so trivial that you would think you're creating a document in Microsoft Word.

So, if you are a blogger yourself, you should take a look at Live Writer.