The qa.debian.org bugs in the BTS use usertags for sorting: http://bugs.debian.org/qa.debian.org . Here's the current setting in case someone wants to change it:

user qa.debian.org@packages.debian.org
usercategory qa-department
 * QA-Department [tag=]
  + Uncategorized []
  + Carnivore [carnivore]
  + DDPO [ddpo]
  + Debcheck [debcheck]
  + Debian Sources [debsources]
  + DEHS [dehs]
  + Jenkins [jenkins]
  + Madison [madison]
  + MIA Tracking [mia]
  + Mole [mole]
  + Package Tracking System [pts]
  + Patch tracking [patchtracking]
  + SVN Buildstat [svnbuildstat]
  + Ultimate Debian Database [udd]
  + WNPP [wnpp]
  + QA Webpages [webpages]
usercategory qa-sort
 * status
 * qa-department
 * severity
usercategory normal
 * status
 * qa-department
 * severity
usercategory old
 * status
 * severity
 * classification
thanks

The current setting can also be retrieved from rsync://bugs-mirror.debian.org/bts-spool-index/user/*/qa.debian.org*packages.debian.org.

To see only bugs with a specific tag point your browser to http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=qa.debian.org@packages.debian.org;tag=<tag_here>

To tag the bugs, use:

To: Debian Bugs Request <request@bugs.debian.org>

user qa.debian.org@packages.debian.org
usertags 12345678 + pts
thanks

or, using the bts command line utility from devscripts:

$ bts user qa.debian.org@packages.debian.org , usertags 12345678 + pts