Today it was announced over at Blogger Buzz that they have now allowed direct sharing of posts to Google+ from Blogger.
To share a post with Google+ all you have to do is:
1. Make sure you Google Profile is linked with your Blogger account.
After publishing your post you will be presented with a a share box asking if you would like to share it with Google+. The share box will contain a snippit of your post and then you can share it with your circles.
Update: I had to manually share this post, but you should check under your Settings, Posts/Comments and make sure Sharing is set to YES. Mine was defaulted to No.