Better hardware means that games can have better graphics, higher polygon counts, richer textures, better sound, etc.
But those don't spring out of thin air. To create more detailed models, you need modelers spending more time creating and animating them. In the original Legend of Zelda, Link was [link url="http://www.nesmaps.com/maps/Zelda/sprites/ZeldaSprites.html"]15x16 pixels big[/link]. In AAA games these days, the main character will be comprised of 30,000+ polygons. They are animated doing increasingly complicated things, which takes a lot of animators, and you've got huge numbers of high resolution textures to be created by visual artists.
Then you've got all the audio. Mass Effect 3 had [link url="http://en.wikipedia.org/wiki/Mass_Effect_3#Audio"]40,000 lines of spoken dialog[/link] and hours of orchestral music. The scoring, recording, editing, re-recording, all takes a lot of time, people-power, and money. And that's not even touching all the programming that goes into the graphics & physics engine, AI, game mechanics, play testing, multiplayer development and balancing. The list goes on and on.
If the next generation of consoles comes out and the games look just like the old generation, people will be up in arms and say "why the hell did I buy this new console if everything looks & feels the same?" To make things better takes more effort. There's no magic "make game more awesome" chip that goes into the next gen of hardware.
So a company spends millions and millions of dollars to develop a game, they need to make sure they make it back. So they do a big marketing campaign with billboards, posters, TV commercials, etc. If spending N dollars on marketing & advertising didn't earn them more than N dollars in revenue, they wouldn't do it. Think of your favorite game that didn't do well commercially, and is a "hidden gem." Chances are it's a hidden gem 'cause somebody botched the marketing.
Big companies like Activision will continue to make big games that cost a fortune, and hopefully earn them a fortune. Just like the big movie houses create blockbuster movies like the Transformers movies, which were critically panned but have made [link url="http://en.wikipedia.org/wiki/Transformers_(film_series)#Box_office_performance"]over $2.6 billion worldwide[/link]. Or like John Carter, which Disney apparently [link url="http://en.wikipedia.org/wiki/John_Carter_(film)#Box_office"]lost about $100 million[/link] on. Win big, or lose big.