The LWN article is a little sparse on details, but on this subject it says "The kernel has to be built without initrd, which takes half a second with nothing in it. So all modules required for boot must be built into the kernel" (emphasis mine).

It looks like we're already there on the "required for boot" front, and we now know that initfs is going away in Fremantle (probably for other more important reasons, but if it happens to improve boot speed at the same time no one's going to complain - same goes for upstart).

More importantly, the current kernel on current hardware takes less than 2" to boot (before initfs kicks in) so there seems to be little point in spending any effort specifically to optimise it further.

Agree 100%.

If anyone cares enough to try it may still be useful to see bootchart output to identify any obvious userland bottlenecks though.