Actually, it's been out, but I finally learned about it today. There are many new features and plug-ins available, and I look forward to testing them out. I learned that Blogger finally did add an API to upload images from an offline blogging client, however; that came out too late for inclusion in this beta. I've always wanted the ability to add images while typing my posts offline, but I realized during my Typepad trial that I rarely use a feature like that. Hopefully the next release will include the API. For now I either have to compose my entries using Blogger's online editor, or compose them offline in Windows Live Writer and upload the images manually after publishing. Blogger always inserts images at the beginning on the post, and I have to cut and paste my text around them. When I'm trying to include screenshots to demonstrate steps in software, this is very cumbersome and painful, and is why I haven't updated my Using Thunderbird for University of Phoenix Newsgroups post, which by far brings me the most traffic out of the 160 plus entries I've made.
I like the ability to add Blogger categories, so I can truly "fire and forget". Up until now, I've been composing in Windows Live Writer, publishing, then logging in and editing my post to add the categories. It's nice to have that extra step removed. Maybe I'll write more now that publishing got easier. Other new features include inline spell checking (apparently hard to do but very useful) and new windows don't open every time you finish one post and want to start on another.
I find Windows Live Writer (beta) to be an adequate and functional free offline blogging client. Blogger does include a WYSIWYG editor, but it's minimally functional and of course you have to be online to compose entries. With Windows Live Writer, I can maintain entries on my laptop and publish them when I choose. If you're looking for a free offline blogging client, give this one a try.
If you don't mind paying, try Blogjet, which I took advantage of a 30 day trial for during my Typepad trial. It's also a very good editor.