Yes, I've run into this too. I use multiple windows throughout my portal each looking to display from CMS using the CMSPorlet, but different queries (locations).
I don't see any ability to associate properties to content in the CMS, nor to query content based upon properties. Is this supported or planned to be supported? I should probably check out Jackrabbit further.
I plan to support this with the CMS, but probably will not have the time to build it in to 2.4.
There are properties already in the CMS - language, title, description, but they are not configurable.
I have heard a few people express wanting this feature. It would be trivial to refactor the backend to allow it, but the frontend would have to need even more work for user input.
Search: Jackrabbit support it and keeps an index on the filesystem, but I have not implemented a frontend for it, as we plan to implement a global search function in the future.