Sun 06-May-12 06:55 AM | edited Sun 06-May-12 06:56 AM by nrothschild
More pixels will never make diffraction issues worse. They just may not add much value (in terms of resolution) at certain narrow apertures.
In other words, worse case, your images will look the same when printed at the same output size. At some point in the future your next camera may have more pixels that you can benefit from, but there will be no other choice and you won't be "paying extra" for something you don't need.