I think whatever everyone thinks on this topic is acceptable.
But I don`t think you should be focusing on ways to keep same people coming by any ways other then proving value. I know it`s hard to do.
I hate it though when some sites have this link on every page "Make this page your home page". That`s so lame. It`s like saying "Marry me" to the person you met for the first time. If I want to bookmark a site - I don`t need a reminder or a prompt. Even less so to make it my default home page. I use blank page as default on all of my browsers on all of my computers. You can`t compete with it so don`t even try. And when you try to make to bookmark your site - you make a lame impression.