Ideally, we keep both boys. Hypothetically speaking, our best attack in the near future might include Arshavin, Chamakh, Walcott, Wilshere and Fabregas. They have enough movement and goals amongst them.
The only upgrades that we might look to would be Chamakh (a better finisher) and Walcott (someone who isn't made of glass).
The truth is the maniac known as Wenger is actually building towards something. A goalie here, a defensive midfielder there, and we have a decent team. Sprinkle with better defensive coaching.