Here are some recent benchmarks comparing Intel's SNA and UXA 2D acceleration architectures offered by their open-source Intel Linux graphics driver.
Chris Wilson of Intel OTC has been banging through hundreds of changes to the xf86-video-intel driver for improving the "Sandy Bridge New Acceleration" architecture. Last week he released the xf86-video-intel 2.20 driver that builds SNA by default and then earlier this week released a new point release. The benchmarks of SNA vs. UXA in this article are from a Core i7 "Ivy Bridge" system with HD 4000 graphics.
The xf86-video-intel release was from last Sunday, however, immediately before the xf86-video-intel 2.20 tagging. The results are just coming out now due to the altered publishing queue schedule while being in Munich since last week. More SNA/UXA/GLAMOR benchmarks will come in future weeks.