Our paper Efficient Consistency Checking of Scenario-based Product-Line Specifications, that I’ve been working on with Maxime Cordy, Patrick Heymans and Amir Sharifloo has been accepted at RE 2012!
The paper proposes a technique for specifying product lines with Modal Sequence Diagrams that can then be checked for consistency using specific model-checking techniques. See more in a recent post on the MSD-to-SMV tool.