You should if you are taking in relatively low light such as in the evening.
All those megapixels into such a small CCD has to pay the price.
Most company manage this by processing the noise away.
If you process too much, no noise but the image quality becomes flat. If you process too little, image is good but noise higher. I think Pentax is one of those who prefer to leave the image intact and let you decide if you want to process the noise away (eg. using Neat). You see once the camera removes the noise and degrade the image, you cannot retrieve the original data. I know Panasonic is very aggressive with this...
That is why I advocate choosing the lowest MP camera that you can find that suits your needs. If you print up to A4, I don't see any need for more than 6MP. If you print the normal 3R or 4R sizes, 4MP will do actually....