Today we disposed of grub in favor of Syslinux for a boot loader. [chad]
Cosmos is NOT based on Linux, Syslinux is a mini Linux used for booting.
We started out with grub. After all, everyone else uses it right? It supports multiboot specification, and is pretty flexible. The docs suck in many places though and binaries are hard to come by. After all, real developers all have gcc on a hot key and love messing around with make files no?
But the final straw was network boot. After getting pxegrub to work, then it failed. Out of 4 computers, it only succeeded on 1. Google turned up many disgruntled users saying "pxegrub is basically broken, use syslinux". So we did.
Syslinux is more flexible than grub, contains easily accessible binaries, and has not just documentation, but good documentation. Finally, pxelinux which is a form of syslinux WORKS. Out of four computers we tried it on, it worked on all four.