udevmonitor will print the received events for:
UDEV the event which udev sends out after rule processing
UEVENT the kernel uevent

UEVENT[1176249417.099493] add      /class/mmc_host/mmc0/mmc0:b368 (mmc)
ACTION=add
DEVPATH=/class/mmc_host/mmc0/mmc0:b368
SUBSYSTEM=mmc
SEQNUM=2650
PHYSDEVBUS=mmc
MMC_CCC=101011101010
MMC_MANFID=00001d
MMC_NAME=SD   
MMC_OEMID=4144

UDEV  [1176249417.121921] add      /class/mmc_host/mmc0/mmc0:b368 (mmc)
UDEV_LOG=3
ACTION=add
DEVPATH=/class/mmc_host/mmc0/mmc0:b368
SUBSYSTEM=mmc
SEQNUM=2650
PHYSDEVBUS=mmc
MMC_CCC=101011101010
MMC_MANFID=00001d
MMC_NAME=SD   
MMC_OEMID=4144
UDEVD_EVENT=1

UEVENT[1176249417.121952] add      /block/mmcblk0/mmcblk0p1 (block)
ACTION=add
DEVPATH=/block/mmcblk0/mmcblk0p1
SUBSYSTEM=block
SEQNUM=2652
MINOR=1
MAJOR=254
PHYSDEVPATH=/class/mmc_host/mmc0/mmc0:b368
PHYSDEVBUS=mmc
PHYSDEVDRIVER=mmcblk

UDEV  [1176249417.249526] add      /block/mmcblk0 (block)
UDEV_LOG=3
ACTION=add
DEVPATH=/block/mmcblk0
SUBSYSTEM=block
SEQNUM=2651
MINOR=0
MAJOR=254
PHYSDEVPATH=/c