Effective January 1, 2007, NASDAQ introduced a single, unified pricing schedule for all equity securities. In addition, effective February 1, 2007, NASDAQ plans to adjust tiers for the unified pricing schedule.
http://www.nasdaqtrader.com/trader/tradingservices/productservices/pricesheet/pricingmenu.stm
http://www.nasdaqtrader.com/trader/tradingservices/productservices/pricesheet/pricesheet.pdf
http://www.nasdaqtrader.com/trader/tradingservices/productservices/pricesheet/pricingmenu.stm
http://www.nasdaqtrader.com/trader/tradingservices/productservices/pricesheet/pricesheet.pdf