Not only will Google's Android Silver Program hopefully be coming out early next year, but let us remember that they also have a goal of releasing their Project Ara modular phones around the same time (January 2015). The reason I bring this up is because online I found that they have a 4 × 7 Endo (sort of like a motherboard) for a model that they label as a "phablet", but if we don't have to be tied to a cell phone provider then we basically will have a modular tablet that we can upgrade piece by piece when newer parts are released.
Also, if we are able to produce successful graphene transistors for our microprocessors to give us some serious processing power on our handheld devices, that would be nice too. So far I only have ran into IBM being mentioned online on creating one at the moment. So if I understood it correctly, if we later on get a module piece with a graphene chip inside then that would be the next step for having powerful haldhelds. Also having to overcome the production process to meet demands as well will be a hurtle to overcome. (Searching online can help find more info on this. I'm not an expert, just posting what I remember reading.) If companies want to hold it off from us, will there be a kickstarter to produce them later on? A user can dream...
Last thing I want to mention since we are talking about Android Silver, is that yes I too believe cost was a huge factor for the success the Nexus devices. Not sure if that was one of the main reasons it has sold so well. Newegg has refurbished Nexus 7s (2013 edition) for $150.00 right now. Which is why I chose the device over all others. Decent specs, open source OS, large Dev community, easy to personalize OS, and all for a reasonable price. Hopefully they take note of all this and keep giving us great devices in the near future.