We were surprised when arriving at the Colosseum today to discover that the "skip the line" suggestion for holders of the Roma Pass did not quite apply. Two months ago, local authorities instituted a security screening, so that the line for individual travelers to get through security meant a wait of 45 minutes to an hour. One of us simply cannot stand in place that long, so he sat out the visit. The other paid 13 euros extra (Roma Pass covered some of the cost) to go on a group tour, which moved through security in about 15-20 minutes.
Major churches also now have similar security arrangements, though the delay getting in can vary depending on the size of the crowd when you arrive. We seemed to get in to a couple of these churches quickly, only to notice a much larger crowd waiting as we left. Once you exit, the only way to get back in is to go through security again.