The power consumption when the CPU and GPU were busy with the OpenArena game was also frightening. There are not results for Ubuntu 8.04.4 LTS since the open-source drivers for the R300 were not in a good state with the Hardy Heron, but as you can see, Ubuntu 11.04 is the biggest loser. The average power consumption is up by 21.3% with this latest release. This is rather disconcerting because that Intel EIST support in Linux has been settled for a while along with the KMS-based ATI Radeon power management support.
Here is a look at the OpenArena OpenGL performance. Interestingly, for this vintage ASIC the performance high-point was back in Ubuntu 8.10 and 9.04 when using user-space mode-setting and DRI1 prior to the Radeon DRM and Mesa switching to DRI2/KMS. With Ubuntu 11.10 the performance may be better based upon advancements in the Mesa 7.11-devel branch and also some forthcoming R300g improvements with the new register allocator, etc.
If looking at a composite of the power data for the ThinkPad T60, yep, Ubuntu 11.04 is definitely in poor shape in terms of power efficiency.