The outage, according to a blog post by Google, was due to a software update that left Gmail users unable to log in or greeted by a blank inbox, with the appearance that all their messages, attachments and chat logs were deleted. Despite having several data centers that Gmail uses for backups, the issue was made worse as apparently those were affected as well. And even though Google said it only affected 0.29% of all its Gmail users, that’s still hundreds of thousands of upset and inconvenienced people.
Gmail back soon for everyone - Official Gmail Blog

Anyone experience this issue? I`ll definitely backup my email now