I've been testing rc1 for a week or so, and about 25% of the time I'm seeing Firefox and Thunderbird getting stuck in 'D' state as they startup.
I've attached the output of Sysrq-T to this mail... system is a dual-core AMD64, and files are on a RAID-1 root partition connected two SATA disks on the on-board NVidia controller. I've had no problems before .24 rc1 Cheers David
sysrq-t.bz2
Description: application/bzip
config.gz
Description: GNU Zip compressed data