There are some major changes in version 1.5 but the biggest of which is the Search & De-spam feature. Now, instead of simply de-spamming and deleting one comment spam (or trackback?), you can search every single blog in your entire Movable Type installation for spam, delete them all at once, rebuild the relevant pages and add all of the extracted URLs to your blacklist.

We?re talking some serious power that you?ve always been lacking.

Furthermore, thanks to Stepan Riha as well as the removal of comment/trackback filtering (which wasn?t needed with Search & De-spam in effect) every function of the plugin is phenomenally faster.

There are many more changes that you can read about in the documentation, so I?ll leave it at that for now.