I think you guys have a big chance to sign kaka this summer. I've posted this allready somwhere else but i'll say it again.
This season he's been playing out of he's usuall position in the team due to ronaldinho's arrival. Milan tried to play with 2 playmakers (kaka + roni) in ancelotti's beloved tree formation 4-3-2-1 but it did not work well. So he started playing with 2 attackers (pato + borriello) and things got better. That means that either kaka or Roni should be benched and neither will except that. Kaka even complaint many times this season that he can't give he's best performance in a restricted role and he's right about that.
I honestly think that he won't last long with milan and there are very few teams out there in europe that can afford him (probably: madrid, chelsea and man city). Madrid are probably after cristiano ronaldo that leaves him with two choices either city or chelsea i guess.....