mirrorless, EVF and other stuff

A few folks keep mentioning that they want mirrorless, EVF or other similar features on the d300 replacement.  I don't understand the point in doing that, on any dslr, but especially on the d300 replacement.  I have yet to see any indication that EVF, mirrorless, Contrast Detection Autofocus (CDAF) and other such features would work well on any DSLR, but especially on a high performance, high speed camera like the d300 and its replacement.

As I understand it, the point of mirrorless is to make cameras smaller.  Okay, I'll buy that notion, but it doesn't make sense for a high performance camera where people are routinely hanging very large, very heavy lenses off of the front of it.  CDAF is far too slow for a high performance camera and the same applies to EVF.  Both of those features will have to improve substantially, just to reach acceptable levels of performance in lower level cameras.  I simply can't imagine trying to use either or both of those features on cameras like the d7000 or d300, where fast, accurate AF is routinely needed by their users.

So, I'd like to see your reasoning, if you're one of the few that want these features on the d300 replacement.  But, please don't respond with unfounded speculation of what you think might happen at some point in the future.  I'm interested in learning why a few folks want these things and that means something tangible, something that is current that demonstrates the capability of the feature.

thanks

Kerry

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