The Nexus 7 was one of the most popular Android tablets due to its very good specs, latest version of Android and most of all, that very low price. But it's now a year old and technology moves fast so it's very slow compared to the current gen tablets available.
Google should be announcing the next gen Nexus 7 very soon and an ASUS rep has confirmed the specs we should expect.
We should expect the same size screen but with a bumped up resolution of 1920x1200, a quad-core processor, 2GB of RAM, 32GB of storage, 5MP rear camera, 1.2MP front facing camera, Android 4.3, 4000mAh battery, Bluetooth 4.0 and other expected wireless connectivity. We should also expect a 4G version.
What will make the next Nexus 7 a killer though would be the price. If Google can keep the tablet at a very low price again it'll be winner.
The current Nexus 7 has seen some trouble over the last year and some articles on the web have stated how the tablet is just deteriorating over use. AndroidandMe have a brilliant article which explains the problems a lot of Nexus 7 owners have been experiencing. I myself have also been experiencing the same with my Nexus 7. Hopefully ASUS will rectify these issues with the next gen.