If you want to download it and give it a try, you just have to go here:
and download the setup file. They ask for your e-mail address, but you can skip that.
The idea of the consumer preview (what they used to call a beta) is to get feedback from real customers, so you don't need to give them any money or be part of an in-crowd to get it. The CP, like all previous betas is time limited. There will come a day when it will simply not boot anymore, so only install it on a test machine.
It is a very cool looking product aimed at being an iPad killer, by bringing the whole world of windows software to a new generation of Windows 8 based iPad-like tablets.
I have to admit, I have not yet had a chance to play with it, but I do have it downloaded and will be installing it to test on my netbook in the next few days. I am guessing though that Win8 will need something more than that to function properly though. It barely handles 7.