I've been waiting for an in-depth interview with one of the Blogger-meisters to come out. Finally, Evan Williams and Steve Gillmore do a multi-page "conversation" about the New Blogger in the latest edition of eWeek.
Many of the questions we see here in the Blogger Forums get answered. The "why" and "where is this going" get addressed --for the most part. Some samples:
On the New Blogger in general terms: "We did a bunch of user testing and are aiming to appeal to a much wider, less technical audience than blogging has ever reaching before. We feel we've made good strides in that direction. The second part is building out some of the community aspects. A few of the major features are comments and profiles, both of which help drive the connections between users, which is of course a big motivation for why people are blogging. And then the third is improving the experience and esthetics of the blogs themselves and the flexibility with what you can do with them. There are the new templates and the new URLs—every post has its own page—and some new flexibility in the templating language."
Some other sections: new tags in the new templates; Atom and RSS revisited; commenting in Blogger and why the decision was made to make comments a separate page; Blogger and Gmail; and much more...
Well worth the read if you want to learn a few things about Blogger.