First and foremost, I should say I'm partnered to a Turk and have spent a few months there; I am not a specialist. While there, I did talk to a few people about the IT climate. So take what I say with a grain of salt.

First and foremost, Turkey is a country of 80 million people. There is a significant amount of variety from person to person, but the tax codes and business rules are not IT friendly relative to other businesses. There is still a non-trivial tariff on computers and electronics, making supplies more expensive than in other countries. From what I vaguely understand it is easier for other companies to evade taxes than IT services, all of which increases the cost of business and makes outsourcing less economical compared to other Eastern European nations. (AKP, the ruling party, is thought of as business-friendly, but I haven't seen any work to really tackle their tax issues.)

Second, Turkey's government is censorship-happy. Nothing like hacker news or reddit would work there, much less something like yelp. (every comment would have to be read, lest someone gets trialed for "insulting Turkishness."

Finally, they don't have a great way for capitalization of projects. Also, the people with money seem risk-averse to new ideas.

Turks themselves are very entrepreneurial, and the few of them that I've known who were developers are generally rather sharp. I wouldn't try to outsource there, however, at this point in time. (Unless I end up there for a few years with a bit of cash and can poke at loopholes. Then, watch out for my new product! :)