I'm with Rex. Getting rid of Arshavin would be an absolutely disastrous move. More so if/when Nasri goes. Shava won't be starting very often anyway; he'll be an impact sub and he'll play when we have injured/fatigued players.
People are forgetting just how good this guy is. We're not replacing him if we sell him. Look at our other options: Chamberlain hasn't played above League 1 level, Ryo has played 12 professional club matches in his life, Campbell has played 8 - in Costa Rica. How anyone on planet earth can seriously suggest we're better off without Shava is beyond me.
Only Nani, Drogba and Cesc got more assists in the world's best league than Arshavin last season. He's a seasoned professional at the very top level. Obviously he was shocking yesterday, but then again so were Ramsey, Theo and Robin (and a few more) - should we get rid of them as well?