The new character engine will not replace Haptek or MSAgents, but add to it. All old characters will be supported if you have the character expansion set installed. The Hal and Zaba characters will be recreated for the new version, these 2 characters will no longer be based on Haptek. The new character engine will include environment rendering with the characters able to interact with the environment. The level of interaction with the environment will be basic for this version, but will lay the groundwork for future improvements.
The next release of Hal will be version 6.2. It will include some minor bug fixes, but the major change will only be the addition of the character engine. It will be a free upgrade to all Hal 6.x users. The brain will be mostly the same for this release. Future brain changes are planned for later releases. This will most likely be the last release to the 6.x product line, work on 7.0 will begin after 6.2.