Sampo touches this annoying issue, analyzing the process of signing for 3rd edition from a developer point of view.
Although it looks safer to have such a system, signing prevents variation and freedom on mobile devices. Process might be complicated to understand even for experienced developers. It takes long time, is expensive and discouraging. Although Symbian Signed has a nice attempt to sign freeware applications for free, it doesn’t go further than to be a nice intention. His idea to certificate companies seems reasonable. However, I do not think it is a complete solution considering small developers, startup companies and can not guarantee efficiency of the process of certification. I am sure it will change by time, but we will keep on suffering until it has a stable and reasonable system.