If you use Gmail as your email backend but prefer a good old-fashioned desktop email client for handling your day-to-day email, you're probably aware that many clients—like Outlook or Mail.app—don't play that nice with Gmail. Here's how to fix that.
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.