I don't think it is possible to be precise about how many followers your blog has and who they are. If someone is following you by GFC (ie Google Friend Connect) then you will see their name in the list of followers – either by clicking their thumbnail in your sidebar or clicking Followers in your Overview page on your Blogger Dashboard. So you do know how many followers you have on GFC. It is not always easy to tie the follower's name up to their blog – sometimes they don't have a link in their profile. And of course, some of those followers may not have their own blogs.
But it took me ages to realize that there can be people following your blog that you have to go looking for. When I learned that you can easily check how many people are following you on Google Reader, I was stunned to find that there were just as many following that way as by GFC.
To check how many are following you, just add your own blog to the blogs you follow by Google Reader – if you are using Chrome, you just click on the big Google Reader icon on the right of the page and then click the red subscribe button in the left subscribe bar. Just pop your home page url into the box that pops up and click add.
You can then go to your blog's name in the list in the sidebar, click it and your posts will show up. At the top under the search box on the right you will see a box called "Feed Settings". Click that and then click View details and settings in the drop down box. This will then show you information which includes the number of subscribers.
You can check out how many subscribers other blogs have this way too – should you be so inclined.
I have yet to find an easy way to check how many people follow by email. If anyone knows could you please comment about it.