I have the same issue.....weird how several people are having this issue.
This time I got a 16gb flash drive and did everything by the book....including the eth0 and the profile....same issue. Boots fine with no key, but isnt ping-able with the key. Also....I noticed that there is a lot of activity on the key, up to point and then it stops flashing....and doesnt do it again. Am going to try netconsole tonight....question about that....
They talk about setting up IP address 10.10.10.x for netconsole....but my home network is 192.168.0.xx.....Do I need to adjust those IP addy's...or use 10.10.10.x...?