I suppose it depends on what's on offer footballing wise, City already have Toure and Fernandinho as a near on cemented midfield partnership so he would probably be contending with Fernandinho for a spot in their start XI, I would assume Garcia or Millner might leave were they to sign another midfielder but it's not like they are short on options there already.
If he came to Chelsea he's more or less nailed on to play each week because the lack of depth in quality options we have.
That said, looking at that City team, it's getting pretty scary with their strength in depth and any player who goes there is going to probably win something most seasons right now so you can't blame them for wanting to go there.