The Linux Kernel and the XORG video rendering have been undergoing some significant improvements in the last year, with Intel’s linux open source team bringing in a lot of refactorings an architectural improvements.
I myself suffered from the lack of support for recent integrated intel gfx cards in notebooks and thus followed the excellent Intel Linux graphics performance guide using the bleeding-edge configuration, i.e. with the latest (non-stable) builds of the xorg / intel gfx drivers and the most recent kernels. However, this configuration was (not quite unexpected) somewhat unstable and had a lot of issues.
This phase is now over. I am happy to say that after upgrading to Kernel version 2.6.32 and the xserver-xorg-video-intel driver 2:2.9.0-1ubuntu2~xup~3 the graphics support is now fast, reliable and stable. Desktop effects are back working like a charm, also in a multi-monitor setup and with sending the computer to hibernation and so forth.
I am quite optimistic that this state might make it into the upcoming Ubuntu release (Karmic), thus eliminating a lot of frustration laptop users have been experiencing with their intel gfx cards.