Just upgraded the simpledream.net/blog install to WordPress 1.5 —> it’s very worth it!
First of all, you can have pages now that are controlled through the main template. Very powerful, could be a solution to the Ward III Neighbors problem of using “entries” as sub-category pages. Instead of various templates to load and change when updating, you can control the look, links, and feel of all your “pages” as if they were posts.
One cool new feature is the Themes section, which allows you to skin one or more pages on your blog, more control over . A new Dashboard was added as the default landing page to your blog admin, so that you can see latest stats on your site and posts from the WordPress Dev blog. It is a bit cluttered visually, though, so it might have to be cleaned up a bit.
The mod_rewrite and comment spam features are very much improved too.