Apple's Phil Schiller is among the smoothest and best-rehearsed executives in the technology business, and his typical presentation demeanor is that of someone enthusiastically reading a press release about the best summer vacation ever. But Schiller's segment of Apple's WWDC keynote on Monday took on an interesting, more aggressive tone as he introduced the Mac Pro. "Can't innovate anymore, my ass," he said — a line directed not at his audience of sympathetic Apple developers, but at the nattering nabobs of negativism that have accumulated at the base of Apple's sliding stock price. Criticize this, Schiller seemed to be saying, as the imposing all-black Mac Pro stood on the screen behind him.

And the new Mac Pro is indeed innovative. It's shockingly small and enormously beautiful in person, and it's the sort of thing only Apple builds: the company spent significant energy reinventing a product for the smallest market it serves, even when pro customers would have been happy with updated processors in the existing model. Apple's strength is that it understands that it's investing in emotional responses to hardware as much as utilitarian concerns, and if the chief criticism of Apple was that it no longer produces stunning, industry-leading computers, the Mac Pro would be the ultimate rebuttal. Schiller should have brought out a mic just to drop it.

But that's not the criticism Apple's actually facing — the company already makes the best laptop and the best all-in-one PC, and many would argue that it also makes the best phone and tablet as well. Apple's stock hasn't slid because it's been putting out uninspired hardware — it's slid because the company hasn't been able to enter any major new product categories in years, and major software efforts like Siri and iCloud have faltered in extremely public ways. A beautiful new Mac Pro does not explain why Tim Cook has spent over a year repeatedly saying the TV market "is an area of intense interest" without delivering a product, or counteract the fact that Apple Maps has become a punchline for late-night comedians.

As it happens, the key problem for Apple has been expressed in perfect crystalline form since December 2012, when John Gruber gave massive exposure to a piece by former Apple employee Patrick Gibson:

Google is getting better at design faster than Apple is getting better at web services.

The only new web services Apple presented at WWDC were iTunes Radio and a browser-based version of the iWork suite, both of which are beautiful but neither of which particularly disrupts the crowded market they enter. iOS 7 features a flashy and controversial new design, but there were few significant examples of how iCloud would expand or enhance the experience of using an iPhone beyond a handful of feature updates, and nothing to address the growing trend of power users with homescreens full of third-party replacements for core apps. The OS X demo highlighted things like better support for multiple displays and a new maps app — that's an app, not a web client. Google Maps' lock on the 90 percent of the market running Windows remains safe.

And while the enormous emphasis Apple placed on design at WWDC was clearly the company playing to its strengths in front of its core audience, neglecting the service side of the equation points to an equally clear danger.

"Most people make the mistake of thinking design is what it looks like," Steve Jobs famously told The New York Times in 2003. "That's not what we think design is. It's not just what it looks like and feels like. Design is how it works."

Under Jobs, Apple did an extraordinary job of changing how entire markets worked: music, movies, smartphones, tablets, laptops, all of it. But it's been a long time since Apple offered any change on that scale, and a visually refreshed iOS 7 and the new Mac Pro aren't proof that it still can, regardless of how bright the neon icons are or how cool those auto-illuminating port labels might be. Until the company can master data and services — a critical component of how things work in 2013 — all that's left for Apple is how things look and feel.