There have been many, many bug fixes. In fact, I can confidently say that half of this release was all about fixing bugs that kept getting postponed in favor of new feature development. I can personally say that bugs I listed early in the development of C6 were fixed in this round  of C7.

No doubt there are some new ones waiting to be discovered. 

When you say "mangle shaders" what do you mean? If you mean importing them from different programs - that's an issue for every 3D software out there since they all use different schema. I do a lot of jumping between c4d, modo, vue, poser pro and carrara. Regarding shader import, even if all the shaders have been converted to texture maps instead of procedurals, the shaders have to be 'fixed' in the receiving program.

Mark