I have a Nikon D40 too, and I love love love it. Love It. No better quality for this level of digital SLR camera. Mine's about a year old and the battery lasts a ridiculously long time between charges. Meets all my needs.
However, it is not a P&S. I have an ancient Canon Elph for my work photography, and it just keeps on going and going like the Energizer Bunny, though the battery is definitely failing after a kazillion recharges. I think 5 years of heavy use is pretty good these days...Mine is about 6 years old, and just now losing steam.