Webwire: Facebook's tech chief departs; Microsoft set to unveil tablet

Facebook technology chief, Bret Taylor, will quit the firm in a matter of months to start his own company, prompting fears over the social network’s future following a recent IPO.
Microsoft is tipped to unveil an own-brand tablet PC later today. The unit is likely to sport Windows 8 – the latest version of Microsoft’s operating system – and run an ARM or Intel processor.
Moody's has cut Nokia's credit rating to junk status after the vendor announced 10,000 more job cuts, citing fears about Nokia's cash position and slow sales of Windows Phone devices.
Everything Everywhere's former chief executive, Tom Alexander, is reportedly in talks with private equity firms regarding a €8 billion takeover of the carrier.
Global web domain registry ICANN inadvertently published the postal addresses of some individuals applying for new global top level domains on its website.
Nigeria's GSM operators – MTN, Airtel Nigeria, Glo Mobile and Etisalat Nigeria – have agreed to pay fines levied by regulator NCC over alleged poor quality of service.
Free speech campaigners Reporters Without Borders are warning Ethiopia’s government is blocking access to Tor, a system that allows anonymous messages. The block follows government bans on using Skype and other voice over IP services – now criminal offences with a 15 year maximum sentence.