After months of basically no action at all, Google has finally updated the Blogger for Android app with a new UI, as well as some improved features and bug fixes.
The new UI takes a page from the book of Holo, as it is now much more in-line with Android 4.0+ functionality. On top of the new interface, the update also adds support for more languages, enhancements to scheduled posts, and auto-sign in when a blog is viewed on the web.
Aside from these additions, some of the Play Store comments indicate that it also fixes a number of annoyances, adding the option to load more than 20 posts, better publishing, and improved settings. Apparently the app no longer runs in the background after it's been "closed," either, which should be a battery saver for some.