[joachim]

A K-3 may entertain (some) existing customers but the real problem is that these numbers are diminishing. Without new lenses it'll be a very rocky road ahead - although I actually like the currently lineup.

 

I think you hit a nail on the head for a lot of the industry: little innovation.  When DSLRs were new and immature, people needed new lenses since digital sensors have different requirements than film.  Due to the move to APS-C or FT, they needed new WA lenses.  Also there were large improvements between successive models (e.g. the move from 6MP to 10MP models, like Nikon D100 -> D200)

 

Today the added benefit from upgrading from a 16MP model to a 24MP model are quite limited (diffraction eats a lot of the benefit).  I personally think that most (not all) people upgrading from e.g. a Nikon D7000 to a D7100 have just to much money.   I doubt many of them will even occasionally print at 50 x 70 cm (about 20 x 28 inch).