Mail tags summary

Hi, I am using mail tags (I hope it's called tags in English version, I 
am using Polish one) to organize my mail. I often use "Work" and "To do" 
tags. It's easier to mark messages with tags instead of read/unread 
status because you can't accidentaly change it by clicking/browsing 
through messages.

But read/unread status has an advantage: it shows as a summary next to a 
folder name. I can see how many unread messages I have in any folder.

Can you add the same functionality for tags? Summary numbers should 
follow color scheme of tags of course.

Best regards, Marcin.