Wow, I am really, really surprised. Especially as Gen. Alexander gave the keynote speech to DEFCON last year, and explicitly said, when asked after his speech:

Q: "[..]Does the NSA really keep a file on anyone? [...]"

A: "[..] Frist, no, we don't [...]"

Absolutely astonishing!

listen/watch here: http://youtu.be/tz0ejKersnM?t=33m2s