With the forthcoming release of Mesa 10.0 there is now OpenGL 3.2 and OpenGL 3.3 compliance. That compliance is for core Mesa and the Intel DRI driver. The Radeon and Nouveau drivers don't have as advanced OpenGL support since most of the upstream GL / GLSL enablement is done by Intel developers and thus the focus on their own driver while the Radeon/Nouveau support usually trails.
With the GL3.txt updates this weekend, this is where things stand today overall for OpenGL 3.x:
OpenGL 3.2 and OpenGL 3.3 is where the Radeon (R600 and RadeonSI) support comes in behind Intel and Nouveau with their NV50 and NVC0 (Fermi and Kepler) Gallium3D drivers.
The OpenGL 4.x state is much direr overall. The Khronos Group published the OpenGL 4.0 specification in March of 2010 and we'll be lucky if we see it in H1'2014, or four years later. There's a lot left to with accomplishing OpenGL Shading Language 4.0 along with other features like the tessellation shader support. OpenGL 4.1, 4.2, 4.3, and 4.4 also have a lot more left by which time it's completed in Mesa there will almost surely be OpenGL 5.0. There's also the possibility of binary Linux GPU drivers by that time supporting the Mantle API on Linux. Anyhow, at least the OpenGL and GLSL support in Mesa keeps advancing. The OpenCL support is also slowly but surely improving.