Dylan, I have to take issue with the title -the figure above clearly shows integration of ASIC with MEMS using the IC packaging technology! Even stand alone MEMS packages use existing lines of IC packaging with modifications to equipments and many new ones. So I would rather stretch the definition of a 'system' as in system-on-package and call the integration as SoC packaging!
The test issue is another story. Both probing and final test of MEMS and MEMS-integrated SoC's are very different from their ASIC counterparts.