strange. in order for me to boot off my SD card, i had to set my bootargs differently. if i tried to use the aforementioned root=/dev/mmcblk0p1, the system would error and tell me that there are a few choices.
eventually, i had to use:
setenv bootargs_root root=b301
and now that i've rebooted, i'm not sure it actually worked. (i wrote a file to the root directory and it's now showing up after rebooting -- i didn't saveenv but rather typed 'boot') anyone know how i can check to see if the FS is set for the SD card versus the internal flash?