If this week had a sound that sound would be "wheeeeee!" or maybe "gnnnnnh!" - that's our impression of BMW's tech-filled and faintly frightening M3 sports car, which can put a smile on even the most sombre face.

But BMW's not the only firm that can change people's moods: Facebook's been at it too, and the internet has a frowny face as a result. It's Week in Tech!

Fury over Facebook feed-fiddling

The internet is ANGRY, and this time it might have a point: Facebook has been manipulating users' News Feeds to try and change people's moods. It's probably legal, but seems rather unethical: "Nobody was asked whether they wanted to participate in what is effectively a psychological study," we report, and it's "arguably irresponsible too: how many of the people whose news feeds were made more negative were people with vulnerable emotional states or mental illnesses such as depression?"

Plasma panels: on borrowed time

Samsung has hammered another nail into the coffin of plasma TV: it's going to build its last plasma set in November of this year, and then it's going to switch focus to 4K and curved TVs instead. Panasonic's already out of the plasma business, and reports suggest that it won't be long before LG stops too. So what kind of TV should you buy if plasma's on the way out? Allow us to help with our in-depth guide to the best TVs of 2014.

Good news for Nexus

Got a Nexus 4, 5, 7 or 10? We've got good news: you'll be able to get Google's super soaraway Android L operating system. The code has already been made available to developers, but we mere mortals will probably have to wait for the official release in September or October.

Microsoft wants your wrist

Does Microsoft want you to wear Windows? It certainly sounds like it: it's working on a Samsung Gear Fit-style fitness device that'll go on sale later this year. It's a fitness tracker rather than a smartwatch, and because this is the New Microsoft it won't just be for Windows Phone users: it'll work on Android and iOS too.

Samsung has a horse

We've looked at two very different Galaxies this week: Samsung's giant Galaxy Tab Pro 12.2 and the teeny-tiny Galaxy S5 Mini. Thanks to a (now-removed) typo in our review we can exclusively reveal that the former is a "power horse", but like many pretend horses it's "let down by the rear… which feels less than premium." Meanwhile the S5 Mini isn't actually that mini: with a 4.5-inch display it's bigger than previous Minis and only a little bit smaller than the full-sized S5.

"Tarmac-trampling triumphalism"

BMW's M3 is "a game changer", says Jeremy Laird, pulling doughnuts in the car park: it's "stupendously, staggeringly, sickeningly quick" and packed with more tech than a terminator. It's the most configurable M3 ever and "an exceptional achievement."

The iPod of the 80s

Imagine a world without the WalkMan. There'd be no iPod, no Wired for Sound by Cliff Richard and no "home taping is killing music" campaign. Sony's smash hit is a terrifying 35 years old, and while the name lives on the iconic tape-based player is long gone.

"There are lessons here for Apple," Ian Morris writes: the WalkMan put Sony at the top of the consumer tech tree, but by the time it made its last tape-based WalkMan in 2009 it was losing money hand over fist. Making music hardware is just like making music: you're only as good as your last hit.