The Chicago-area retail vacancy rate has continued to fall as new and existing tenants eye the market for expansion. And while the city has been especially hot, with the fitness, theater and restaurant segments driving much of the activity, the suburbs have been more of "a mixed bag," according to Taylor Johnson client Transwestern. In a recent interview with REJournals.com, Transwestern's Patrick Owens discussed challenges and opportunities facing landlords as big-box retailers like Sports Authority go out of business and others look for ways to differentiate themselves from - or embrace - e-commerce.