I just had a bit of a scare after updating to udev-181, but all is well now, finally. (I hope :)
In addition to the separate /usr problem that has already been discussed at length here, there are other important changes in udev-181 to be aware of. First, I had to add two new items to my kernel config: CONFIG_DEV_TMPFS (which I thought I'd had for years but didn't) and CONFIG_TMPFS_POSIX_ACL. I also elected to make the devfs automounting, but I don't think that was really necessary. Second, don't forget like I did to update the udev initscripts with etc-update or your machine won't be able to find the udev files in their new locations (just like mine didn't) and none of your kernel modules will auto-load, either. Oh, and of course you need to pre-mount /usr before udev starts if you have a separate /usr partition -- but you already knew that ;)
