Description of problem:
When installing from a USB stick containing the DVD image, the installer does not find the packages on the USB stick and falls back to a network install.


Version-Release number of selected component (if applicable):
Whatever is on the F15 install media.

How reproducible:
1 out of 1, but I think always - I peeked at the anaconda source, and it seems to systematically ignore all non-CDROM media.

Steps to Reproduce:
1. Download Fedora 15 DVD (I used i386/i686)
2. Install unetbootin
3. Use unetbootin to put the downloaded ISO on a >=4G USB flash drive
4. Boot flash drive and try to install
  
Actual results:
After partitioning, the installer prompts for network configuration and proceeds with a network install, completely ignoring the 3+GB of packages on the flash drive.

Expected results:
Anaconda locates the package tree just like it does when booting a real DVD, and allows the system to be installed without consulting the network.

Additional info:
I had to use unetbootin because the Fedora LiveUSB creator could not use the DVD image (although the Windows version of it was able to use the netinst image).