On a recent -CURRENT at the time of this writing (2014-09) and confirmed for 10.2-STABLE.
Suspend/resume works
Video suspend/resume requires newcons (vt(4)) and DRI2 to be loaded
Brightness keys work; acpi_ibm(4) and acpi_video(4) work
The mute, volume controls work, keypress events in X11 need to be mapped to XF86Audio{Mute,Raise,Lower}Volume
With a bit of tuning, idle power drain can be held in 6.5—7 W range, which yields over 10 hours of autonomous uptime with a fresh 9-cell battery
Updating the firmware is possible after converting the ISO image using sysutils/geteltorito (to boot it using an USB stick):
# geteltorino -o bootable.img bootable.iso