Downtown Atlanta gears up for dueling Friday night concerts

ATLANTA - Downtown Atlanta commuters are gearing up for a potential traffic nightmare Friday afternoon. <br> <br> Two competing free concerts are being held around Centennial Olympic Park. Meanwhile, the annual telecommunications trade show Supercomm - with more than 40,000 attendees - winds down. And thousands of men are expected for the start of the two-day Promise Keepers conference at Philips Arena. <br> <br> The weekly On the Bricks concert at Centennial Park could attract 35,000 to 90,000 people. A competing rock station is having its first concert, Downtown Rocks, tonight in a large parking lot north of the park.