The past few years STI has been slowly creeping into mountain bike components, too. It started with XTR (Shimano's top of the line) last year, or maybe the year before. Now they also have it on the lower levels. The shifter and brake is the same lever. "Squeeze" to brake and uhhh... shift to shift... How can that be explained? The down side (in mountain biking, anyway) is that you have to have Shimano compatible brakes (AKA Shimano brakes).

By the way, does anybody know what STI means or stands for?