Hmm... strange.
I overwrote the values in /sys/devices/virtual/backlight/mbp_backlight/brightness and /sys/devices/virtual/backlight/mbp_backlight/actual_brightness and now the brightness seems to be properly saved on suspend.
Hmm... strange.
I overwrote the values in /sys/devices/ virtual/ backlight/ mbp_backlight/ brightness and /sys/devices/ virtual/ backlight/ mbp_backlight/ actual_ brightness and now the brightness seems to be properly saved on suspend.