This past weekend over 150,000 Internet users woke up to find their Gmail inboxes, contacts and chat conversations gone. The issue, according to Google, was caused by a storage software update that introduced an unexpected bug. But while the company has since begun restoring data from tape backups and will likely offer some form of compensation where applicable, the incident served as a reminder that no matter how reliable some cloud-based services are, they are certainly not infallible, and thus it might be prudent to have your own backup ready just in case things go amiss.
But you can still go back to the old layout if you prefer.
Overall, this looks like a decent UI update for people that use multiple Google services.
Spam runs rampant on Gmail, but you have options.