For those that have multiple Gmail accounts you have been able to use multiple sign-in on your desktop for a while, now this feature comes to the mobile interface.
The other updates include the ability to set up a mobile specific signature and access to the vacation auto-responder.
Of course the multiple sign in and signature are both features that your standard smartphone will have in its native app so I am unsure of the use of those and whilst the vacation responder is a nice touch is its use not just for those forgotten occasions.
Looking at the bigger picture though I am expecting these are just the start of Google preparing for the day when Android has no native email client and merges to the browser only Chrome OS.
The full article can be found here.