Public betas for vb4.1.x releases have been very short. Or even moving from alpha to beta to release in a week. You can see it live on various sites, like https://www.vaultwiki.org/activity.php
I really hope that PP will add activity stream support. This would be a massive added value for me, as it would bring Photopost out of the shadows into the daily activity stream of my members. People would start using my gallery again.
The activity stream is pluggable.