Google Nexus 7

The Google Nexus 7 is an Android 4.1 ("Jelly Bean") tablet with a seven inch display, available for pre-order in most English-speaking countries right now and due to start shipping in the US in July.

This form factor has proven very popular with the Amazon Kindle Fire, in part because a 7" tablet is easier to hold than a 10" one, and in part because a 7" tablet is also very much cheaper to buy. With prices starting at $199 in the US (with a $25 Google Play voucher at launch) and £159 in the UK (with a £15 voucher), the Nexus 7 is a very affordable device.
The display on the Nexus 7 is a 7" 800 x 1280 pixel panel with scratch-resistant Corning glass. There's a front-facing 1.2 megapixel camera for video calling but no camera on the back. Inside is a powerful quad-core Tegra 3 processor coupled with 1GB of RAM. The Nexus 7 has a choice of 8GB or 16GB of internal non-expandable flash storage, which isn't a massive amount, and therefore it's a shame that there is no microSD slot.
Google's main competitor here is Amazon rather than Apple, and it's likely in part that Google have seen that Amazon's Kindle Fire product is very good at driving consumers to make more purchases (such as books and videos) from Amazon, and Google would quite like a slice of that business for themselves.