Currently the follow function does not follow the activity of the members you follow. Except for the newsfeed, but not many seem to be using the newsfeed anyway. To truly follow someone, you need to be kept up to date on the persons activity. This means all posts, comments, profile changes, trophies received, etc. should trigger an on-site alert. I was actually amazed to find out that xenforo does not give on-site alerts for the activity of followers. That is what I expected any follow function to do.