I think Tipsy and Almagro fall out. Delpo and Soderling replace them. I can't see anyone else falling out, though someone like Raonic or Isner probably comes from behind and overtakes whoever would be #10 (probably Fish or Ferrer).
So, nobody is saying Fed will fall out of top4? (I'm not saying he will, it's just curious for MTF standards)
Don't see it at the moment although all the guys in the top 10 give him trouble these days. I think he'll give it one last big push next year, possibly picking up one more slam, and then post US Open 2012, will begin to slow down and start slipping down the rankings as he skips more and more tournaments.
Dolgopolov has no mental for a consistent top 10 spot. Raonic can defientely surprise everybody and rush into top 10 by the year-end although he has loads of points to defend in the first two months of 2012.