Arsenal, and Arsene Wenger for that matter, are a strange one. They clearly have some money to spend this summer, the £40,000,001 bid for Suarez clearly indicates that, yet so far seem to have added nothing to last years squad. Indeed they are actually letting players leave, with Chamakh and Gervinho rumoured to be out the door. Also, when you look at the Arsenal squad you see a team with numerous holes that need filling, should they really be spending a huge chunk of their budget on just one player when they need to strengthen in both fullback positions, in goal, in midfield (they need a strong, ball winning player) as well as upfront?
Arsenal face the very real risk of dropping out of the top 4 for the first time in over a decade, Spurs ran them close last season, and have made steps to improve their squad, if Arsenal stand still they'll be left behind.