Google's +1 Button is now live. Here's the official video. I've put some additional information under the video to help you out if you're having trouble installing the code for blogger/blogspot.
You can go to the Google Webmasters Website to see instructions on inserting the code. It looks like this:
(You'll need to copy the code from the google website--I've posted it here as a picture because I can't post the code within my blog post--blogger interprets it as code instead of text).
I had to tweak the instructions a little. Here's what I would recommend:
1. Go to your blog's control panel and click "design"
2. Now click "edit html," and "expand widget templates." It will look like this:
3. Now you'll need to find code for your post header (if you want the button on the top of your post). It should look something like this:
You can try this first on a crash test dummy blog if you are a little nervous about messing with your blogs html code.