ASMlib was never REQUIRED for ASM... I have been doing ASM on Linux, Solaris, AIX, HPUX for 5-6 years and have never used it - but of course it was only available on Linux. I have build in the neighborhood of 15-20 Linux clusters (~75 clusters overall -10g,11g).
Just make sure you partition off the first 1M (start your ASM partition at cylinder 2). Use udev/multipathd to ensure devices are available on reboot and you should be good to go.
using udev would be just a useless workaround/way-out and you need to perform few un-necessary steps as well.
If you are going to have oracle11G R2 188.8.131.52 and above, then go for ASMLIB and forget about the complexities created by udev. ASM will take care of disknaming and their identification on system reboot.
I have always wanted ASM deployed but with the OEL 6.3...wasnt sure if the ASM rpm was already deployed and part of the OEL kernel...
So its good to know that it is and all we need are the oracleasmlib and asm support rpms...