I also have a real problem with being so 'philanthropic' with my personal data. If it's aggregated into a truly anonymous grouping, that's different. But when it's the government, or the Red Cross, or Planned Parenthood, or even NPR collecting personal data on me, I have to that I am adamantly opposed.
Read the Big Data link in Ishanahan's post, "Big Data is our generation’s civil rights issue, and we don’t know it" for a better explanation of what I see as the logical, legal outcome of sharing personal data.
As individuals, we can decide to share our data with the best of motives, but after that, we have absolutely no control over how any for-profit company uses what we give them.
I don't trust Amex or Verizon to operate transparently any more than I trust to government to do so.
"No pressure, no diamonds." - Thomas Carlyle