There is no indication that it's changed to be more transmissible. Have you read the report that the Dallas nurses gave to the nurses union? Here it is, if you haven't:
http://www.latimes.com/nation/la-na-ebola-dallas-20141014-st...
It's a private hospital and is self-policing when it comes to preparing for and implementing CDC protocols. Based on the allegations, they clearly had not made the necessary preparations, so the nurses were very poorly protected and almost certainly came into contact with excretions from the patient. The fact that the nurses had to release this information via a union that didn't represent them because of fear of whistleblowing probably has a lot to do with how this situation came about.