At the same time, Ian is hoping to deliver a Mesa 7.5.2 stable release for those users wanting more mature, stable code. However, Mesa 7.5.2 will likely be the last release in the Mesa 7.5 series.
In order to accomplish the Mesa 7.6 release on less than a week's notice though, Ian is setting the blocker bugs as high where as Mesa 7.6.0 will be released as long as there are no build failures and no very serious regressions compared to Mesa 7.5. This may mean that a stabilized Mesa 7.6.1 release will get out the door quite soon.
The Mesa 7.6.0 / 7.5.2 release proposal from Ian can be read on the Mesa3D-dev mailing list.
Mesa 7.6 provides support for a number of new OpenGL extensions with its software rasterizer and the Intel i965 driver mostly, there is the rewritten Radeon/R200/R300 driver that uses the buffer manager (a.k.a. the Radeon 3D driver re-write), GL_EXT_framebuffer_object support for ATI when using the TTM memory manager, proper OpenGL 1.5 support for the ATI R300 series (and VBO + OQ support), and the assembly shader rework. This in fact is just a small portion of the changes. Mesa 7.6 is quite a huge update compared to Mesa 7.5, which was just released in July.
On the Gallium3D side, Mesa 7.6 is the release that delivers the OpenVG state tracker, OpenGL ES 1.1/2.0 state trackers, networking support, and plenty of other work that has built up over the past few months.
While Mesa 7.6 should be quite a nice release, work on Mesa 7.7 is already underway.