david winston, betsy myers.o you both for being with us. >>> an update on that breaking news out of pittsburgh. police at the scene of what is called a hostage situation at the gateway center downtown. a person who answered the phone at the front desk says no one has been evacuated yet. we got an update from police just into the our newsroom. among the things we know, at least 20 emergency vehicles surrounding the building. this has been going on since about 8:20 this morning. this is a very well-known building. one of the prominent buildings in the skyline of pittsburgh. 24 stories high. we'll keep our eye on that breaking news out of pittsburgh. also today -- both campaigns will be at the aarp convention in new orleans. in about an hour, president obama via satellite then paul ryan in person. the obama campaign released a new web video slamming mitt romney on medicare. >>> i'm not a victim. you know? sorry he sees me as a victim. he would be a tragic president. >> nbc's ron mott is live in new orleans and, ron