Thanks for that Andy, maybe I'm allowed to comment a bit. For instance from the first site
This is a bit of misinformation, the pixelmania arguments are typically Nikon that refused to keep up in the megapixel race. It's more complex and also a function of pixel quality and lens quality. Indeed it is useless to increase pixel count if the lens is the critical limitation for more resolution but often it is not. Smaller pixels are obviously struggling with signal noise ratio but that doesn't mean that the optimum solution is in the low pixel count. And a high pixel count allows you to crop, the more the better.
Tinypic seems out at the moment but when it's back I'll demonstrate how important that is.
Let me illustrate the importance of pixel count with this picture:
this is on 15% of the real size which is 12.1 MP of the Canon 450D, you see that I used it in the current photo challenge in a crop of 50% size. That'sthe closest I could get that picture with the 300mm zoom
This is a crop on 100% size:
So if the camera was only on say, 3.5 MP, the best I could have done was this:
So more pixels is indeed more resolution (lens depending) and a priory dismissing the higher pixel count is an unjust generalisation.
Then the high ISO. Apart from the fact that natural light is miles ahead of flashlight for a nice harmonious shot, there are also several occasions that the normal numbers fall short. If you want to do fast sports hand held with a telelens on a gloomy day or marcoshots from life insects, the situation requires high shutterspeeds and small apertures, allowing only a little light to the sensor. That's also where high iso numbers save the day.