Can I setup custom domain publishing, without losing my Followers?This is one concern where the perception is much worse than the reality.
The Following concept involves two services.
- The links between your Followers profiles, and your blog.
- The newsfeed ("Atom" / "RSS") subscription setup for each of your Followers.
Your Followers profile relationship is against your blog, using its BlogID. As long as you do not switch to publishing a different blog (with a new BlogID), the Followers profile relationship with your blog will remain intact. This is the case for both a normal renaming of the blog (BlogSpot to BlogSpot URL change), as for a custom domain publishing (BlogSpot to non BlogSpot URL change).
Your Followers subscription relationship is against the URL of your blog. Since a custom domain publishing involves forwarding of the BlogSpot URL, to the domain URL, the subscription relationship will remain intact, after the migration process is complete. A BlogSpot to BlogSpot URL change may involve some effort by you to retain the subscription relationship; this does not need to be done, for a BlogSpot to domain publishing change.
You will need to note the custom domain transition period, which affects Following. There are portions of the Followers database which do need to be separately updated, by Blogger, after the Transition period is complete. During Transition, you should expect to see your Followers gadget temporarily unavailable. Shortly after Transition ends, your Followers gadget should be updated, and it will resume operation - and your new readers will be able to Follow your blog, with no concern.
Other than during the 3 to 4 day Transition period, your Followers should expect to see no problems, in any relationships with your blog. As always, I'll simply advise you to manage the migration, for any custom domain change.