I live and work within 30 miles of the orthodox triumvirate: Lakewood, Borough Park and Monsey. In those 3 cites I would estimate at least 85% (maybe up to 95%) keep kosher.

Interestingly enough I talk with a woman who works with the Orthodox Union (11 Broadway, NYC). We've had many conversations about Kosher trade marks. There are greater and lesser degrees of Kosher. Supposedly the OU (U withing the O) is the mark that every one recognizes as kosher. Other trademarks may or may not be considered "kosher enough" by some. Personally I think there is a lot of politics involved.