I did notice the fresh install of 12.04 it didn't pickup my software raid as it did in 10.04 and 8. I didn't think anything of it because that's what I wanted.
Come to think of it, it also didn't prompt to use the HDD's in my MD's either. Again not an issue for me, because I'm not using them.
root@moon67:~# fdisk -l
Disk /dev/sda: 160.0 GB, 160041885696 bytes
240 heads, 63 sectors/track, 20673 cylinders, total 312581808 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xe6c4e6c4
Device Boot Start End Blocks Id System
/dev/sda1 * 63 312575759 156287848+ 7 HPFS/NTFS/exFAT