The 1.3 development is coming along very well. With todays release 1.3.3 there is a pretty reliable implementation for the old problem of how to determine the number of unread items of each feed and folder in the feed list.
What is missing is the calculation of the unread count for search folders which is pretty problematic. Search folders are internally realized with sqlite views and every item modification can change the unread count of each search folder. So the only way to update the unread count of all search folders after a user interaction is to recount it for each search folder or to determine which of the search folders was affected and to increment/decrement the unread count appropriately.
The disadvantage of both solutions is that the unread count update processing time increases directly with the number of search folders. Choosing to recount on each update additionally decreases performance with a growing total number of items, while the delta processing depends on the matching rule complexity.
Anyone knows a good design pattern for realizing such a dynamic counting functionality?