I don't expect Robinho to stick around. He won't content with finishing 5th or 6th place on the league table.
That fucking towel head has to understand this is football, not fucking baseball or hockey. Money is for the most part the last thing on players minds; fame and reputation for their legendary clubs (Kaka for AC Milan as an example) is 100 times more important. Why hasn't Lavezzi left Napoli? He's been linked with some of the biggest clubs, but he refuses to leave. Why? Cause people at Napoli make him feel like a God, and wants to make an impact there.
I think players leave clubs for a new challenge only once they feel they've done all they could for the team they're currently playing with... obviously, you get the exceptions though.