Today's Tech: Microsoft turns to Halo for Windows version of Apple's Siri and Marissa Mayer breathes fresh new life into Yahoo

Dell stockholders have approved a plan to take the company private. Based on a preliminary vote tally, founder Michael Dell has enough support to acquire the company with Silver Lake Partners. The $24.9 billion (£15.75 billion) deal means Dell stockholders will get $13.88 (£8.78) per share in cash. The deal was approved by those who hold a majority of Dell's shares, which is required by Delaware law. The deal is expected to close by the end of the third quarter of Dell's fiscal year 2014. It was first proposed in February, but faced a challenge from Carl Icahn, who made his own bid for the firm with Southeastern.

Yahoo now has 800 million monthly active users, up 20 per cent since Marissa Mayer took the helm of the then struggling tech giant in July 2012. Mayer announced the milestone this week at the TechCrunch Disrupt conference in San Francisco, noting that 350 million of its monthly active users are on mobile. If you think the rise is related to Yahoo's recent acquisition of Tumblr, think again. Mayer added that the figures do not include Tumblr. Instead, most of the growth comes from the company's core products like search and Mail, she said. On mobile, Yahoo Mail is one of the company's most popular properties, along with news and finance. Internally, Mayer has placed a greater focus on the company's mobile products, increasing the size of the mobile team by a factor of 10 since she took over.

Twitter will be the next big Internet firm to go public. The micro-blogging site this week quietly filed for an initial public offering with the Securities and Exchange Commission, before announcing the move - of course - on Twitter. "We've confidentially submitted an S-1 to the SEC for a planned IPO. This Tweet does not constitute an offer of any securities for sale," the company tweeted from its @Twitter feed. The move comes shortly after Facebook chief Mark Zuckerberg was quizzed at this week's TechCrunch Disrupt about his company's lackluster IPO. The social network filed for an IPO in January 2012 and went public in May 2012, but hasn't exactly taken Wall Street by storm.

According to new reports, Microsoft is pursuing its own version of Apple's Siri and Android's Google Now, which will be based on a character from the Halo video game series. As reported by ZDNet and WMPoweruser, the next version of Windows Phone - 8.1 - will include a voice-activated assistant known as Cortana. Cortana has been featured in a number of versions of Halo. A Microsoft spokesman has said that the firm had nothing to announce. But reports about a Siri-like app for Windows Phone have been making the rounds for a few months now. Cortana on your phone will reportedly be much like Cortana in the video game world - learning and adapting to your behaviour. It will tap into Windows and Xbox as well as Windows Phone.