You can decline to state your age but you can't hide from this new facial recognition software from Omron Corp: it can tell the sex and age of people!
A computer screen displays the sex and age of people as determined by face-recognition software developed by Omron Corp. at the CEATEC technology trade show in Chiba, Japan October 2, 2007. The Japanese text reads: (L to R) "Woman 20-39 years, Man 20-39 years, Man 20-39 years".
Link - Be sure to check out Cellar Image of the Day for more fascinating photos (don't miss their 6 years worth of archives!)
http://coldchiliandhotchilly.blogspot.com/2007/09/maquinas-analizadoras-de-nuestra.html
I remember the first few generations of voice recognition - those were horrible - but they did become much better over the years.
You can just see where the technology is taking us the next couple of decades.