Android 4.2 (Jelly Bean): Android 4.2 is not that big of a deal, especially compared with the last version,
Ice Cream Sandwich Android 4.1, which brought Google Now (an honest-to-God revolution) and Project Butter (a huge improvement in regular use of Android phones). Android 4.2 has: Miracast, which does basically the same thing as Apple's AirPlay. It'll require a box or a new kind of smart TV to work, though LG says all of its future smart TVs will have it (and LG's TVs are quite good). The new Android also has a screensaver mode, which, fine, whatever, and multiple user support so all members of a household can use the same tablet while keeping their apps and settings and stuff. And there's a panorama mode called Photo Sphere, which lets you take a complete spherical view of your surroundings. That'll actually make for some pretty cool photos, I think.
Oh, and Google Now is better! It'll now reach into your Gmail - I know, I know, creepy, but Google Now always straddled that line between creepy and useful - for stuff like flight and hotel information.
Nexus 10: Made by Samsung, start to finish, the Nexus 10 is the first 10-inch tablet with the Nexus name. "Nexus," remember, denotes an Android product not made by Google but made under very close supervision - the idea is that this is the pure vision of Android, from its makers. This is what Google thinks an Android tablet should be, along with the smaller Nexus 7. It's hardware is undeniably great; a higher pixel density than even the iPad 3's "Retina Display," 2GB of memory (that'll help it run tons of apps at once), a quad-core 1.7GHz processor, and a lighter body than the iPad 3, at 1.33 pounds to the iPad's 1.44. And in the US it's US$100 cheaper than the iPad, starting at US$400 for the 16GB and US$500 for the 32GB. (There's no LTE model yet, and no 64GB model - and Australian pricing TBA.)
Of course, what really matters with tablets isn't hardware, but software, and Android tablets have never quite figured out how to cajole developers into making lots of quality apps fit for the larger screen. Hopefully Google gets that process going!
Nexus 4: The new Nexus smartphone, this one made, for the first time, by LG. Good news first: super-dense 4.7-inch screen (good, I mean, for folks with Dikembe Mutombo-sized hands), fast quad-core processor, 2GB memory, Miracast support, wireless charging. Cool!
Now the bad news: The Nexus 4 is, right now, a T-Mobile exclusive in the US. It's only available in 8GB and 16GB sizes, and doesn't support superfast 4G LTE, because the T-Mobile network doesn't super superfast 4G LTE. That...kind of sucks.