Which question are you asking? Are Blogspot blogs Dofollow or do you get PR juice from them? There are three types of Blogger/Blogspot blogs. Kewl huh? The newest version of Blogger which is hosted at Blogspot, yes and no. You have to hack the template, but can only remove Nofollow from the Author link. Links in the comment body are nofollow, and cannot be changed. The 'Classic' version of Blogger cannot be hacked. They are nofollow and nothing can be done about it. It is also hosted at Blogspot. If anyone using Classic says it is Dofollow, don't believe them. Then there is the Classic FTP version of Blogger. These blogs are FTPed to servers underneath the blogger's control. They can be hacked with PHP to remove nofollow completely. There are only two Classic FTPed blogs that I am aware of that are actually DoFollow ... and you can find them pretty easily. Go ahead, Google it as an exercise. Do they provide link juice? Why don't you try commenting on one and see.
blogspot default as nofollow, but some of the member change it to dofollow. In this case, you will get the PR juice if you comment on the blogspot with dofollow
I have posted on How to Remove Nofollow From Blogger / Blogspot / Wordpress here: http://forums.digitalpoint.com/showthread.php?t=668499
Yes. It's nofollow. But, so many people are using hacks to make it dofollow to encourage readers to comment.
By default, they are nofollow, but I notice alot of blogger/blogspot users have disabled nofollow on their own, more so than wordpress users.
Curious one that! Don't know if that is true or not, but I have personally helped around 50 of them to do it. Not necessarily. Some of us did it to send a message to Google et. al. We personally want the option to decide for ourselves.