Thanks to a successful Make-it-Happen campaign the 4.1 release comes with a much improved and super flexible approach for running Civi's critical back-ground processing tasks. These tasks include keeping membership statuses up to date and sending renewal reminders, sending scheduled CiviMail mailings, sending pledge payment reminders, and more. I've spent the past 10 days testing and documenting the new "consolidated cron" functionality, and the good news is that I think it fulfills the promise of providing a convenient and friendly way to administer and run all the required tasks for a site.
The "bad" news is that these improvements are NOT backward compatible. The set of PHP scripts which were previously used to run these tasks have all been deprecated (and moved to a 'deprecated' directory). This means that all CiviCRM-related cron jobs will stop working as soon as any site is upgraded to 4.1. (Yes, a loud warning will appear on the screen at the end of the upgrade process.)