<aside>
What is being said about n8XX devices is what i've felt for a long while with my n770. I now have the new hotness with an n900, but I don't think thats any reason to abandon the old working hardware. part of the reason i haven't reflashed my n700 after mucking around w it so much is that i'm worried about repos and such just not being there.
</aside>

I think the tagging and categories can run in separate tracks and could even be developed separately as long as you don't build in conflicting calls, etc.

Below is my first crack at the tagging portion also added to Brainstorm - waiting for it to complete saving...

• Threads can be tagged by any user
  
• Any user can create Tags
  
• Tagging is not anonymous - Any user Tagging a thread is listed next to the tag in the thread - this prevents unhelpful tags being added w/o some way to address unhelpful posting behavior
  
• Tags can be added or removed dynamically via the search results UI - similar to how some shopping sites allow you to narrow down or broaden your choices based on criteria

This would allow users to customize content on things like n900 Browsers Text, and as long as either the thread starter or people reading the thread had tagged it appropriately should be able to find what they are looking for.

I imagine there could also be a mix of tags and search terms, but as was said above, tiny chunks that can be executed on efficiently and effectively.

hth