[citation][nom]sykozis[/nom]Nope, that's for the optional displays....10.1" LCD or 13.3" LCD...so, Camikazi is right, it's an expansion port.[/citation]
Yup, the connector supports LCDs. It also supports stuff that hobbyists love like GPIO, PWM, ADC, UART, I2C, and SPI.
[citation][nom]article[/nom]"...6 USB 2.0 ports..."[/citation]
Actually, it supports 7 USB ports: 6 full-sized USB host ports and 1 micro-USB slave port (supports mass storage and ADB).
It also has a MIPI CSI connector for attaching bare camera hardware and has a eMMC connector (separate from the SDHC card slot).