I know I haven't posted in a while, but found a couple things that may be contributing to the CM7 boot issues. I noticed that the partition sizes specified in boardconfig.mk don't seem to match up with the sizes listed in 'cat /proc/partitions'. I'm not positive I'm converting blocks to disk space correctly, but I believe the partition values listed in boardconfig.mk are smaller than they should be. (do your own research and confirm)
Don't know if anyone's noticed this already, but just thought I'd throw them out there. Even with these settings updated in boardconfig.mk, my phone still wouldn't even try to boot so there's still something else going on, but I think they should be updated regardless.
Edit: Thought I found an issue related to the kernel command line too, but I think it's okay after all.