Have you visited BMA's Trails Page? Their trails page has information on Boulder Area trails that I've never even knew existed! Each trail page contains lots of good detailed information on the trail like it rating, length, elevation gain, location, conditions, photos and a description of the trail. This section of their website has probably 40+ trails listed and organized by location. Great resource for area cyclist wanting to try something new, visiting from out of town or want to get the details on what they just rode.
In addition to the trail information the BMA's website has what could become "the" place in Boulder County to check up on trail conditions before heading out on a ride! Their trail status page has the ability for others to describe the current trail conditions and in addition to see what tweets there are for #boco_trails