First, the blog entries can now be edited with a full blown WYSYWIG editor. No need to fiddle with < > and html tags.

Second, blog entries now support tags: tags are one-word descriptors that you can assign to any blog entry. As del.icio.us put it,

Tagging can be a whole lot easier and more flexible than fitting your
 information into preconceived categories. If you want to post an article about a little
 known Greek philosopher, just tag it with "philosophy greece" or whatever other tags
 you'd want to use to find it again. You don't have to rely on the designer of the system
 to provide you with category for Greek philosophy. You just make up tags as you need
 them.

Have fun exploring these improvements and, as usual, report problems and give suggestions for improvements on the forum.