I'm really excited about the new Project Aura phones that Google are working on - phones get older every year, and to make them upgradeable like my desktop rig really excites me. Imagine being able to have a Lumia 925-style ultra-thin phone, but then being able to snap on a 1020 camera module!!! I think MS should definitely look into this, it's not an easy feat to make components swappable like that but it's not impossible either.
I watched this video and been reading about Google's project Aura here. The Concept is neat but, I don't think it will take off.
When people decide they want a new phone (unless your a iSheep), you want a new look, better display and smoother/faster performance. A lot of people (including myself) looks at a phone how it was designed and how it looks (a lot of "art" goes into designing a phone these days).
Sure, you can spend the $300 to upgrade the CPU/GPU to a modern spec, then prey that Google offers the drivers for it, then you have to worry about carriers supporting all aspects of the phone. like Verizon does with the ICON or other devices, you could get a new CPU but, wait 3-6 months before you can actually use it.
Most people are in that disposable world thing (90% of smart phone buyers). Their old phone is OLD, they go out and buy a new one, plain and simple. A Modular phone would not be really a great concept for 90% of the people, maybe forums like this (hobbyists) but, for the masses, no way.
The other side of it will be cost, who would actually go out and spend $200-300 on a CPU/GPU upgrade (because standalone that is what it would cost), when you can get a full new phone, with new look, same or better specs for under $200 with a 2 year contract ?
Nice concept but, I think that is all it will ever be is a concept or if released, it will be a special order that is ONLY GSM unlocked and that would leave a good % of people unable to use it...
And as Smartphones go, if it's not going to sell for the masses, it will be a failure...