No. There is no SD slot. I purchased the 32gb Nexus 10. If you want additional storage, you can purchase a Wi Drive. I purchased a 128 GB Wi Drive and it works great. You can use it with WiFi or Bluetooth.
No SD Slot, No Problem. there is an app for that called Nexus Media Importer. It's $2.99 in the google play store. Or as listed below, you can get a Wi-Fi storage device like say the Seagate GoFlex Satellite Mobile Wireless Storage 500 GB USB 3.0 External Hard Drive for around $170.00.
Question for all - does anyone know if the micro USB supports reading/copying of files from a thumb drive? If appears from the other responses that there are a number of ways to move files onto the Nexus 10. However, I have an application that would require me to copy files from physical media. This is supported from the Samsung Galaxy tab through their micro-USB. If anyone has an answer, would appreciate your input.