mind you that's why the Pentax bodies are A LOT heavier than the D40. . .
Without lens or battery, the K100d is just under 100g heavier than the D40. I don't know if I'd consider that a LOT. The D50 came in near the K100d's weight, the D70 exceeded it, and I don't recall too many Nikonians complaining that either was unbearably heavy. No, the K100d is heavier mostly because of the shake reduction system (the K110d, without shake-reduction, actually weighs only 9g more than the D40... and retains a top LCD and an autofocus motor). In use either Pentax will however be heavier due to using AA batteries. But my point is not about how good a Pentax is or how well it compares to Nikon, that's not what this thread is about... my point is, an AF motor really does not add that much weight. It's a cost-cutting thing, why pretend it's anything else?
I agree we shouldn't tell people "Don't buy the D40", you should simply point out the potential limitations. But is it really going to put people off photography? No, at worst it puts people off a Nikon D40. There are other cheap entry-level bodies which buyers can consider, including Nikon's very own D50 (as Sabbath999 recommended) which I still see on sale in several places.