ExoMars landing site downselections

It hasn't been that long since the Mars Science Laboratory landing site downselection meeting; it was quickly followed by a meeting in Europe on ExoMars, which is currently planned for a 2011 launch. BBC News posted a story on the ExoMars meeting that included a list of ExoMars' short list of possible landing sites:

• Mawrth Vallis - an ancient valley covered with light-coloured clay-rich minerals
• Nili Fossae - large eroded surface fracture partially filled with clay-rich debris from a space impact
• Meridiani Planum - ESA is looking at two different sites on this plain located two degrees south of the equator
• Holden Crater - an ancient lakebed with layered sedimentary deposits
• Gale Crater - an impact crater with exposed layered deposits

Sound familiar? I'll remind you of the short list of possible sites for MSL: Nili Fossae Trough; Mawrth Vallis; Southwest Meridiani; Jezero Crater; Holden Crater; and Terby Crater. MSL is designed to search for past habitable environments on Mars; ExoMars is designed to search for past life, so there's certainly overlap in their mission goals. Still, you'd expect the two missions to have somewhat different criteria for both the safety and science sides of landing site selection. I wonder how the final choice of MSL's landing site will affect the choice of ExoMars' landing site (if at all)?