Jeez o pete, how hard is it to write a frakkin thank-you note? And yes, I DO believe the email propsed in original post is an acceptable idea - it's the acknowledgement that counts.

I can only imagine non thank-you'ers are the same people who put shit back on the supermarket shelves without regard from whence it came, creep up to my elbow in line at the bank to peek at my deposit slip, and clip their toenails in their cubes. Manners!