There was alot of of talk/flames on the LKML about devtmpfs. Looks like a big push for this was for embedded devices, android, etc. Since I read that it may give a boot time speed up, I was slightly intrigued. http://lkml.org/lkml/2009/4/30/182, yes…it is an old topic but it finally was released in stable .32 kernel.

So, bootcharts:
bootchart-2.6.31.6.png 39 seconds
bootchart-2.6.32-no-devtmpfs.png 37 seconds
bootchart-2.6.32-devtmpfs.png 37 seconds
bootchart-2.6.32-openrc.png 26 seconds (devtmpfs)

So, where is the real win here? Well, as I wrote [before][5], use openrc.

[5]: http://blog.jolexa.net/2008/09/22/gentoo-improve-boot-time/