Originally posted by Rondec I just don't buy that megapixels make that much of a difference if you are framing well. Particularly not, if you are comparing landscape photos, shot with good lenses, at the sweet spot on 24 megapixel cameras (D610 versus K3). If, you go up to a D800 (much pricier than either of those two cameras), you will see a difference, but once again, it will be most noticeable if you are not framing well.
There are certain types of photo where you will see a clear difference, those would particularly be with regard to narrow depth of field and high iso. But the OP did not mention either of these as a goal of his.
I think I know what Jay means about having more megapixels.
Its an additional option for perhaps an additional photo out of one shot.
So from an environmental shot of my girl playing at the playground, I'd also get a close up half body portrait because I have the option to crop to that.
Its not about poor composing, its about an additional option.
But personally, I've never found that big a need to crop that much out of landscape photos.
If I need an longer shot, I'd have used a longer lens.
For my kids shots, maybe a bit more often... somehow... (maybe they those are more spontaneous shots with less time to compose and frame)
IMO, what we are discussing here is not what the OP was looking out for...