I think the donation system is not enough put forward for Free Software (Free and Open Source Software).
With some software (Free (FOSS) or no-Free), we can't propose customized features or services, in exchange for remuneration, for businesses. And some developers (principally those are not customary with philosophy of Free Software) are not make free software of this type because with their software, principally for the general public, they want to earn a little money.
Nokia will propose a service that allows users to make, with very little click, donations to the developers / teams they wish to support.
Discussion thread: http://talk.maemo.org/showthread.php?p=354950