Thanks for the link D5100, very interesting!
Unfortunately diffraction is going to be tough for technology to get around. The tips are good ideas, but ultimately there are trade offs which cannot be eliminated. Since we cannot get around it (to my satisfaction) I have to consider it. On this sensor resolution becomes compromised by diffraction at f7.4, a bit low for landscape photography. This is of course very acceptable for most other applications and for those that shoot under f8 as a norm. With this in mind, for landscape work, additional resolution, say beyond 20mp (on a dx sensor), will be compromised by diffraction.