i think what might count in our favour is that we've always had strength in depth in midfield - wilshere, Ramsey, Song, arshavin rosicky, diaby, walcott - all top quality players. we need to reinvest that money on our defence - a centre back and a left back, with the 50+ mil we get from cesc and nasri we should get the best available to us - but will wenger spend big? doubt it.
I am also looking forward to a midfield of Wilshere and Ramsay. However, Nasri and Cesc are difficult to replace.
I also wonder where Nasri will fit into a Man City team. Balotelli, Tevez, Aguero, Dzeko, Silva, Toure already occupy all the attacking any team needs.