For many years Mercedes was the leader of automotive market. Mercedes was the introducers of many technologies. What you see in a Mercedes will be available in other cars sooner. I still remember the times when Mercedes was the first company to offer five speed automatic gearbox! Many competitors like Audi and BMW offered five speed automatic gearbox later and in many model they were quite late.
Time has passed and competitors started to offer more than Mercedes. Yes, that's true! Unfortunately, Mercedes stuck on five speed automatic gearbox and still that's the only gearbox if you have four cylinder engine. Of course, Mercedes is offering seven speed automatic in V6 and V8 engine range but in cheaper models, gearbox is cheaper also!
A few days ago Audi announced that wide range of models will have eight speed automatic gearbox! Yes, eight not five or seven! It means, Audi will be more economic, more efficient, more silent and more, more! And it also means, Mercedes is started to losing the game.
What Mercedes is doing is like selling a new computer which has a hard drive only capable of storing one picture of you. Yes, Mercedes is offering a new computer with 500 MB hard drive. Hopefully, as far as I heard, they will be offering seven speed automatic gearbox in near future. But I don't know how near it that :) I hope Mercedes will remember to count after five :)