Davygee: let´s look at sales history.
3rd generation (NES, Master System) ----> 70 million consoles sold.
4th generation (SNES, Megadrive/Genesis) -----> 70 million consoles sold.
5th generation (PSX, N64, Saturn) -------------> 140 milion consoles sold.
6th generation (PS2, XBox, GC, DC) ---------------> 155 (+DC: 165) milion consoles sold.
There was a growth in every single generation till today + we´ve got a mainstream system (Wii) which is likely to expand the audience (and the audience already expands at the moment we talk) so why do you suggest the highest sales for a console could be 40 milion? Even in the best case this would bring us to 120 milion consoles sold which is a drop of 35 milion... how can you see this happening?