SID,
Sorry but I do not know where you get your info from. Currently there are 15 EU members, 7 of these have to pay for visas to Turkey these visas range between roughly $12-25 (depending on Euros, Pounds, Kroners, whatever). That means that half of the EU countries pay for visas. When the EU expands in a few months, 80% of the EU will need to pay for visas to Turkey. There is no such thing as a blanket "block" exemption (for example most EU countries are VWP for the US, however for example Greece is not).
The $100 was NOT in anyway reciprocal. Besides the fact that any visa was in violation of a 1955 agreement signed between Turkey in the US, Turkey started this tit for tat idiocy in 1985, and was responsible for the two increases before the $100 level.
It should also be mentioned that the minimum visa issues to Turkish tourists to the United States is for 1 year, and until recently 10 years was the noem. Currently the average is 5 years. The maximum for a US citizen is three months. Hence for a year a us citizen is still now paying $80, while a Turk pays $100. If the Turk gets a 10 year visa it is $100, the US citizen was paying $40000 and now would/will pay $800.
A recent article in a Turkish newspaper (I would have linked it last week, but it was in Turkish) claims that even excluding the estimated tousist losses due to 9/11, etc. That Turkey lost in excess of $80 million in US tourist revenue attributable SOLELY to the higher visa fees (Several cruise companies pulled out partially due to this) while the $80 difference in visa fees raised for the government an estimated WHOPPING $12 million.
Also remember that Turkey actually taxes its own citizens with a practical exit visa of appx $50 EACH TIME THEY EXIT!!!! This is also in violation of Turkey's 1997 Customs treaty with the EU. The rescinded it for a few years but brought it back a couple of years ago.