The Upload: Your tech news briefing for Friday, May 8

The dark underside of the revolution in medical technology is that security is usually an afterthought, if it's considered at all. Now researchers at the University of Washington have proved another nightmare scenario by taking over a tele-operated surgical robot, Computerworld reports. One of the problems is that the device communicates with the remote control console using a publicly available protocol that's easy to hijack.

NSA data dragnet broke the law, appeals court rules

The U.S. National Security Agency's program to collect domestic telephone records in bulk was not authorized by the Patriot Act, an appeals court has ruled, disagreeing with the position taken by the Bush and Obama administrations. The NSA's phone records program violates U.S. law because it "exceeds the scope of what Congress has authorized." The action Thursday sends the American Civil Liberties Union's lawsuit back to be heard by the U.S. District Court for the Southern District of New York.

Tesla's new Powerwall home battery seems to be a hit

The Powerwall home battery introduced by Tesla last week for consumers who want to store energy generated by renewable sources such as solar panels is a hit, according to CEO Elon Musk. He said that 38,000 batteries have been reserved on the company's website in less than a week. The Powerwall comes in two flavors, according to PC World: A 7 kWh model costs $3,000, and a 10 kWh model costs $3,500 and serves as a backup solution.

Fitibit IPO filing shows a strong pulse

Fitbit, the maker of wearable activity trackers, has filed to go public and revealed some strong sales numbers in its pitch. The company seeks to raise as much as US$100 million in listing on the New York Stock Exchange under the symbol FIT. Its filing with the securities regulators reveals what has been a healthy business: it sold roughly 10.9 million devices in 2014, more than double what it sold in 2013 and more than eight times as many as it sold in 2012.

Uber wants Nokia's Here mapping business

Uber has joined the companies competing to buy Nokia's Here mapping business, and may be bidding about $3 billion, the New York Times reports. The maps service will help Uber as it extends beyond ride-hailing and into car-pooling services, which requires more complex routing across multiple locations, and also into general deliveries. Also bidding for Here, according to the New York Times' sources, is a group of German automakers, BMW, Audi and Mercedes-Benz, which may be teamed with Baidu in the effort.

Facebook: Contrary to belief, our users see a diversity of opinions

Facebook is far from an "echo chamber" that fills your News Feed with posts that are in accord with your own opinions, according to a study by the company's scientists that was published Thursday in the journal Science. Nearly a third of what appears in your feed cuts across ideological lines, Facebook said. The effect is mostly the result of having friends and relatives whose views you disagree with. Maybe for Facebook's next study it can look to see if there's a link between how often someone is "unfriended" and how frequently they spout off about topics on which they are woefully ignorant.

Spotify said to be eyeing video streaming

It's musical chairs in streaming media. While Apple's Beats gets ready to move in on Spotify's music business, the music streaming service is planning to get into Web video, reports the Wall Street Journal. The newspaper said Spotify has been contacting companies that produce video for YouTube with an eye to buying their shows and co-producing original material. Spotify has a press event scheduled for May 20 in New York but hasn't said what it's about.

Watch now

On World Tech Update this week, Microsoft's Surface 3 tablet goes on sale, the FAA approves special drone flights and an autonomous car hits the road.

One last thing

Android Wear beats Apple Watch hands-down in one category: the freedom it offers designers to come up with creative, custom designs for watch faces. Here are ten nice examples of the state of the art so far.