Many softhouses are complaining about the develop cost for 360 and ps3(more ps3), what would be done to make the next gen have near the same evolution of specs in the consoles and have lower development costs?

Honestly i think it has to do with perception of the console by its audience. Xbox 360 and PS3 games continue to focus on graphics (for the most part) and thus companies are always trying to one up each other but next gen if Consoles advanced on technology again but had the standpoint of playing good games and not so much on graphics developers could have a good looking game thats fun to play but they dont have to spend millions making it look like real life.

Basically dont pressure companies to make the next KZ2 or Gears 2. M$ and Sony need to market their systems as casual friendly not powerhouse consoles.

Hopefully that made sense and you can see wht im trying to say

I don't think it's possible.  i think the videogame industry will eventually mirror the movie industry in that a few major studios will create the vast majority of the more expensive movies.  It's already happening now even though some people seem to want to believe that trying to stop technological progress and sticking to SD games is the way to go.  The current trend has been going on since the first videogame appeared and will continue to go on long after the current generation of consoles are forgotten.  So blaming anything on the current HD consoles or thinking that things will be different next generation is being shortsighted when you look at the big picture.