Less expensive Macs (or should I say, A less expensive Mac model does not necessarily mean a "low priced" Mac. A $799 Mac "netbook" would be less expensive than a MB, but it would still be an expensive netbook.
Apple is going to sacrifice margins, brand caché, materials quality,etc. Turning the Mac into a commodity might increase market share, but it would not be a satisfying experience for anyone. It would be akin to slapping a Porsche logo on a KIA.
Better for Apple to give people more value for their money, i.e., faster chips, GPUs, intro new technology, etc than try and play the low price game.
At any rate, I'll believe it when I see it and not a second before.