The backlight of my X61t screen does not come on again after resuming from S3. I have to use the following quirks to make it work:
<match key="system.hardware.product" prefix="776796U">
  <merge key="power_management.quirk.s3_bios" type="bool">true</merge>
  <merge key="power_management.quirk.s3_mode" type="bool">true</merge>
</match>
in /usr/share/hal/fdi/information/10freedesktop/20-video-quirk-pm-lenovo.fdi

With and without the quirks applied, resume sometimes fails with a hard-lockup. I suspect the fault is the video driver as well, though I have not yet been able to trace the lockup problem. I'll file a separate bug as soon as I'm sure it is a bug in the driver.

Here is some information about my environment:
Ubuntu Gutsy
Driver downloaded at Fri Feb 22 11:41:25 from git://anongit.freedesktop.org/git/xorg/driver/xf86-video-intel
xorg: 7.2-5ubuntu13
kernel: 2.6.22-14-generic
lspci output:
00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:19.0 Ethernet controller: Intel Corporation 82566MM Gigabit Network Connection (rev 03)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Contoller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
00:1f.0 ISA bridge: Intel Corporation 82801HBM (ICH8M-E) LPC Interface Controller (rev 03)
00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03)
00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03)
02:00.0 Memory controller: Intel Corporation Turbo Memory Controller (rev 01)
03:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG Network Connection (rev 02)
05:00.0 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev ba)
05:00.1 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 04)
05:00.2 Generic system peripheral [0805]: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 21)

xorg device section:
Section "Device"
        Identifier      "Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller"
        Driver          "intel"
        BusID           "PCI:0:2:0"
EndSection