At the LSB F2F Spring 2011, a number of proposals were discussed that related to modularization: the idea of splitting the LSB into multiple pieces, each of which could be targeted by ISVs and/or distributions. These proposals boiled down to two major ideas: exposing our current modules to end users, and a more radical proposal called "Runtime Profiles".
The proposal to expose our existing modules is covered in Modularization50. This page covers the more radical proposal. It was originally proposed to be part of LSB 5.0, but nothing about runtime profiles is necessarily tied to any particular spec version, so it has been pulled out of the feature list there.
These derive from the Linux Application Checker's ability to report information about compatibility, through knowledge of the presence/absence of packages and versions, with various distributions as well as the LSB. Since we have the information to determine compatibility, can we provide that information at build time to allow ISVs to target particular sets of distributions for compatibility?