I was thinking along very similar lines myself. If I am locked out, for whatever reason, do I re-apply, or just let things lie for a while? I too have already finished my MSc, so that also isn't a place of improvement for me. But I don't think there's any such thing as a record that can't be improved. GRE scores can (almost) always go up, and there is always room for more intern or work experience, publications, or presentations in your area. Also, as is so often said, applications are currently at an all-time-high place. As the unemployment rate drops (and apparently it's now at a two and a half year low), application numbers should drop as well, which may mean slightly better chances next year. I don't know, hopefully this is just a theoretical for both of us. But I wouldn't take the Northwestern decision to spell doom, not at all - as we all know, admissions decisions often follow little logical rhyme or reason.