I have recently acquired a Nexus 7 and I really do like this tablet. My first go of Android was on a Galaxy Mini GT-S5570, and I was not impressed. The phone would not last a day, even if I just left it in my bag. I thought at the time it was more down to the phone rather than the OS, but to be sure I wanted to have another try.
I was documenting some config/setup that I am have done on the Nexus, and I needed to take a screen shot (The post will follow shortly that I needed it for). Thankfully it is very simple to do, all you have to do is :
Press and hold the volume down and the power button at the same time. The screen will take the snapshot and then it fades away.
Once you have the screenshot you can then edit it in an application like Skitch from Evernote, Skitch is great for adding comments to photos, screen shots etc. It' cross platform and will sync with Evernote.
I am always interested in feedback so please feel free to add any comments, or you can mail me here. If you would like to submit a quick tip with full credit and links back to your site then also feel free to contact me.