While AE and PR are big products, Encore just comes free with PR. So its obvious that you will hear a lot more about AE & PR.
See the feature list of Encore CS5 http://www.adobe.com/products/premiere/encore/
It has exciting features for all the users. 4K mastering, AVCHD output, 24P project, cross platform, 64 bit background transcoding by AME are certainly going to help complex project users
Blu-ray authoring is finally practical for more than just a very basic project. The multi-page menus are very good, and can make popup menus just like the big boys. It also seems easier to keep track of the pages all in one Photoshop file.
True, no animated buttons, you can only have 18 buttons, and your selected and activated button images and colors are limited by some DVD restrictions. But there is enough to work with to create some very nice results. Encore is also more stable and reliable.