Week's Winners and Losers: Tesla Rolls, Coca-Cola Roils

There were plenty of winners and losers this week, with the world's top brand in electric vehicles rolling out a compelling new feature and an NFL star taking the world's largest soda distributor and a cereal giant to task.

Netflix (NFLX) -- Loser

Shares of the leading premium video service slumped Thursday after it posted uninspiring quarterly results. Revenue and earnings fell just short of analyst expectations, and when your stock has more than doubled this year, you can't afford to not be perfect.

The most surprising nugget in Netflix's report was that it added just 880,000 more domestic streaming subscribers than it lost during the period, making this Netflix's worst showing on that front in more than a year. Netflix blamed part of the slowdown on newly distributed chip credit cards that resulted in folks unable to automatically renew their monthly subscriptions, resulting in a spike in involuntary churn. Some skeptical Wall Street pros aren't buying it.

Tesla Motors (TSLA) -- Winner

We are getting closer to a future of self-driving cars. Tesla vehicles received a software update this week that allows the car to kick into Autopilot mode. Similar to the airplane feature bearing the same name, the mode enables drivers on steady-moving freeways to let Tesla's sensor-driven computer take control. It respects the space around it, and a simple tap of the turn signal results in a lane change at the next viable opportunity.

Tesla's Model S has won critical raves for years as a car. It's ironic that a car that is reportedly so fun to drive is also the one leading the way to driving itself. Drivers still need to take control on slow-moving roads and city streets, but Tesla says that the truly autonomous car is now just a couple of years away.

Coca-Cola (KO) and Kellogg (K) -- Losers

The NFL's leading quarterback is speaking his mind on sugar consumption, and it's not what beverage giant Coca-Cola and cereal star Kellogg want to hear. Tom Brady got a bit animated in an appearance on a Boston sports radio show. He said that Coke was "poison for kids" and that all of the money that Coca-Cola spends on marketing amounts to quackery.

%VIRTUAL-WSSCourseInline-1003%He also took a bite out of Kellogg, blaming Frosted Flakes as one of the many reasons for this country's obesity problem.

Coca-Cola and Kellogg fought back, defending their products. It's true that Brady's reputation may be shaky after his alleged involvement in the Deflategate scandal involving underinflated footballs, but he's still one of the league's biggest stars. When he speaks, folks -- and particularly impressionable children -- listen.

Playboy -- Winner

In a surprising move, Playboy announced that it would no longer publish naked pictures of women in its magazine. Playboy will rely more on its articles than pictorials and centerfolds come next year, and going the PG-13 route does have it benefits.

Playboy realizes that it can't compete with free online porn. Access to titillation is too easy in this digital age, and even an iconic brand like Playboy hasn't been immune.

Cleaning things up will be a gamble, but it's one that will probably result in a broader range of advertisers and possibly even its readership. It's the right call. Playboy had just better hope that it didn't wait too long to do this.

Twitter (TWTR) -- Loser

If "pink slips" were a trending hashtag this week, it's probably because Twitter is cutting some of its employees loose. The social media giant dismissed more than 300 of its workers Tuesday. One can argue that layoffs are a natural part of the corporate cycle, but the trimming process has a funny way of drying up morale.

It's not just some employees who are packing their things and moving on. JMP Securities downgraded the stock. Concerns about slowing usage growth -- and not the layoffs -- are at the heart of JMP's lukewarm opinion on Twitter as an investment.

Motley Fool contributor Rick Munarriz owns shares of Netflix. The Motley Fool owns shares of and recommends Netflix, Tesla Motors, and Twitter. The Motley Fool has the following options: long January 2016 $37 calls on Coca-Cola, short January 2016 $43 calls on Coca-Cola and short January 2016 $37 puts on Coca-Cola. The Motley Fool recommends Coca-Cola. Try any of our Foolish newsletter services free for 30 days. Check out The Motley Fool's one great stock to buy for 2015 and beyond.