I’ve been using the Nexus 7 for a couple days now. Here are some thoughts.
7 inch size is perfect for one handed reading in any orientation. Vastly superior reading experience than an iPad which not only requires two hands but makes reading lying down near impossible.
The screen is no where as nice as the new iPad (expected) but definitely better than the iPad 2 (not expect). This is only exacerbated by the terrible compression on some of the stock wallpapers.
Jellybean feels like a nice evolution of ICS. (Last android device I owned was a Nexus S). It even feels more modern than iOS 5. The larger screen real estate also helps in certain places such as widgets and the task switcher.
Chrome is wicked fast. Browsing is now on par with an iPad in my opinion.
For the price, I opted for the 16gb version, it is the best tablet on the market. I have an original iPad 1 and a kindle touch and the Nexus will replace both of them.
If/when apple releases an iPad mini, I have no doubt they will sell like hotcakes. The form factor is simply better suited for some tasks. I just hope some of those customers will give the Nexus 7 a shot. It may impress them.