Windows 10 upgrade free for owners of Windows 7 and 8.1

Fresh news from Microsoft's painfully aspirational Windows 10 briefing .

. Owners of Windows 7, Windows 8.1 and Windows Phone 8.1 will be eligible for a free upgrade to Microsoft's upcoming OS. The free upgrade will be available throughout the first year of Windows 10's life.

That's a pretty big deal—Microsoft no doubt realises that people are hanging on happily to Windows 7, but the chance of a free upgrade could prove tempting. For PC gamers, it'll mean free access to DirectX 12, which won't be supported by Windows 7.

We'll have more from the briefing as it happens. For the most part, it's just a series of people saying "devices" in different degrees of sincerity and urgency.