We're planning to release ]po[ 4.0 in September/October. The new version will be based on OpenACS 5.6, as the most important change. For details about other enhancements please see http://www.project-open.org/documentation/project_open_roadmap.
We're soon going to send out a mail to all registered ]po[ users asking for feedback etc. Would you be interested to a) sell ]project-open[ yourself or b) provide support for ]po[? Then please answer to this post, register at www.project-open.org or send a mail to firstname.lastname@example.org.