I'm not sure about this but here's an interesting paper trying to categorize AS into different types including socially anxious ones. I'm not sure how valid these categories are?
They haven't been validated. I see some glaring problems but they're useful observations. I remember the authors weren't classifying Asperger's alone but social communication ranging from normal to profound autism. The main Asperger's group was the Emerging social communicator (ESC) group, with some falling in the Weak interactive social communicator (WISC) group. I appear somewhere in between these groups (maybe solid ESC) - more on the ESC side but not enough to fit well.