Open-Source Intel developers have long been working towards a tear-free Linux desktop with proper vsync support. For Sandy Bridge and Ivy Bridge hardware there's still been some tearing issues, but they hope to soon finally have it solved.
Beginning with the Linux 3.8 kernel (yes, 3.8) paired with a brand new xf86-video-intel DDX driver, the last troubling issue that caused tearing on Sandy Bridge graphics and newer will hopefully be eliminated.
Chris Wilson released the xf86-video-intel 2.20.12 driver this weekend (he also released the 2.20.11 driver on the same-day too, but that was plagued by an immediate UXA problem). With this driver using secure batch buffers when available, finally the driver can hopefully performance updates to the scan-out while being synchronized to the refresh rate for Sandy/Ivy Bridge graphics card. With the synchronized scan-out working, this will hopefully eliminate tearing problems.
On the downside, however, this tearing elimination with legacy vsync through secure batches comes at "quite a power cost" as the GPU needs to be kept out of its power-savings mode.
The xf86-video-intel 2.20.12 driver release announcement can be read on the mailing list