The Development carrier board has 4 USB 3.0 ports and one USB 2.0 port that can only be used in device mode. You should be fine. If you have the production module, it will depend on your carrier board. You will likely want a powered hub in any case. Also note that USB cameras will likely not perform as well as CSI cameras, so if you do have a production module, there are carrier boards out there designed for multiple, high performance, CSI cameras.