I have been using Blogo to post to Twitter and this blog for some time now, and it really is an amazing piece of software.
One thing that is really nice is the Safari integration. For example, when I am viewing a Flickr photostream, set or tag page, I can click the Send to Blogo bookmark, and Blogo is smart enough to ask if I would like to include a link or a slideshow (see below). Blogo also has built in support for other sites like YouTube. Very nice.