Apple now ships the entry-level 16GB WiFi iPad 2 with 2-hour extended battery life. Along with the new third-generation iPad, Apple in March began selling a lower-priced, $399, iPad 2. In the UK, the iPad 2 sells for £329.
The new iPad 2 features 32nm A5 processor giving a better battery life. The test results from Anandtech showed that iPad 3 buyers would get extended endurance from their new tablets.
Unfortunately, buying an iPad 2 now doesn't guarantee you get the better iPad, as inventories of the older model are still around. It is difficult to predict whether your newly purchased iPad 2 is an older model or the refreshed model without taking it out of the box and checking for the new model.
However, according to Anandtech, "The newer iPad 2,4 units should come with iOS 5.1 preloaded, while any older iPad 2,1 stock may have 5.0.1 or older. But the most accurate way to tell is by looking at what a utility like Geekbench will tell you about the hardware."