So if you use more than one Twitter handle, now you can toggle between accounts on your Android app without having to log out and log in again.
This is a feature the Twitter iPhone app has had since before it was acquired by Twitter, back when it was still just Tweetie. But support for multiple accounts is a feature that had yet to appear on the Twitter.com web app -- much to the chagrin of power users and Twitter marketers -- and much to the relief of third-party clients that have based their businesses on multi-account support features.
Push notifications, on the other hand, might seem redundant given the fact that Twitter notifications also appear in the Android notifications bar. (For iPhone users, push notifications have been around since last fall.) Still, if you're the kind of Twitter fanatic who wants -- nay, needs to be interrupted every time to get a new @reply, you'll appreciate the new feature.
You can download the new Twitter for Android app now from the Android Market. As always, it's free of charge.