DSLRs will probably never die the same way Medium format camera's have never died. They fill a niche in the pro market.
I have no real desire for a DSLR - but I would like something like my D7i with interchangeable lenses.
Who says an interchangeable lens cameras HAS to have a optical prism view finder ?
Yes the current generation of EVF are slow and grainy but I love the concept.
The current crop of 5MP prosumers all seem to have the same 'defects'. -
Grainy and slow EVF
Slow and unpredictable auto focus
An EVF that makes manual focus difficult.
And all to a certain degree get so noisy at higher ISO settings that you tend to avoid using it.
The DSLRs tend not to have these defects, but then the BODY costs twice to three times that of the 5MP intergrated Lens prosumers. You get what you pay for.
Presumably the next generation of 'prosumer' will pull in some of the technology from the pro DSLRs, like autofocus systems that actually work and interchangeable lens mounts..
Higher resolution and faster updating EVF wouldn't go astray.
(Which requires a better EFV display chip, faster processor chips and image capture chips with a faster 'live' readout mode).
It is quite possible the current 5mp prosumers all suffer from a conflict between the needs of a live readout to run the EVF and the readout data required to do autofocus - the end result that neither are done well
The DSLRs all use a seperate chip that takes light from the mirror - meaning they stop actual focus data collection once the mirror is up....