Well there are the GL, Strix, G771 Some other models that are really other than Gaming models repurposed as gaming I don't remember all the different models. are slim models that's the trend slim and slimmer personally I really like the G series and the great cooling systems that come with them. If I need something to travel around with on planes etc. I'll bring a tablet

This is just natural progression, they will keep changing the same basic shape till they revamp the whole line. The same thing happened with the G50, G51,G71,G72. Their respective series look similar though 4 or 5 models. Now they have a great design from the G53, G73 series and improved upon it. There's no reason to change it at the moment, the design itself has come a long way. Like Clint mentioned the cooling designs are great.

I still think the G46vw was the best design yet, 14 inch is very portable and still has some decent hardware. They should revamp the G46 before they get rid of the stealth design cues.