If you have an Android based smartphone and are located in the U.S., you either can already see or should see soon an update that gives the store a facelift. It is supposed to resemble the Honeycomb interface, which is the 3.x release of Android currently on tablets like the Xoom. That UI will come to smartphones under the title Ice Cream sometime in the 4th quarter.
The store also allows you to purchase e-books and rent movies according to Business Insider. While some movies will be $1.99, many will be in the $3.99 range. For that price, you are paying for the convenience of having a movie on your phone. HD movies from Amazon rent for about $3.99-$4.99 on a big screen TV. The advantages of taking a movie with you though are obvious. You can stream the movie, which would be best over Wi-Fi or a 4G connection, or you can "pin" the movie to your device where it will be downloaded so you can watch it offline, like in an airplane.
As for e-books, Google claims to have a library of over 3 million titles, so you should be able to find something to your liking.
The updated Market is only for devices with Android 2.2 or higher. The interface has been revamped by making it easier for you to find the top apps or related apps. You can also see apps that are trending, which will give you a heads up to apps that are rapidly gaining in popularity long before they actually become chart toppers. By keeping an eye on this list, you'll be able to grab future top apps long before your friends or co-workers and when they finally ask you several weeks later if you've heard of app XYZ, you can look down on them and say "Yeah, I've had that for weeks. What rock have you been living under?"
For now, this is for U.S. customers only. No word when these features will roll out internationally, but you can bet that is on Google's roadmap.