It would be a disaster if Arsenal signed Kaka, he's an overweight has-been, he couldnt hack the pace of La Liga so I've no idea how he'd manage in the Premier League.
I also don't know why he sold Eboué last week. He could have kept him til after the Udinese 2nd leg, played him in that and then sold him. Galatasaray aren't in Europe (so he wouldnt have been cup tied) and their season doesnt begin for 2 weeks.
Wenger needs to get himself over to Germany sharpish and use all the Fabregas, Touré, Nasri and Adebayor money to sign some great players from the most difficult league in Europe.
It seems like Arsenal aren't going to spend big this year. I think they should go in for Mertersacker or Westermann (might cost a bit) to shore themselves up at the back, even Van Buyten could do a job at the back and all of these except Westermann could be had for around £10m or less. If they want to spend big and invest in the future they should sign Andres Beck (the Soviet-born German at Hoffenheim) or Neven Subotic (at Dortmund) but these guys are young and it would cost a bit to get them - that said they might be cheaper than Walcott v2 they signed last month.
In midfield they need a ball winner, I'd go for Rolfes of Leverkusen (not cheap but better than Vidal) or I'd even by Höwedes of Schalke and play him in a holding role again he's fairly young. Upfront he should try and sign Schürrle from Leverkusen, they paid Mainz €8m for him in September last year, I'd try and tempt Leverkusen with a €13m bid. Then sign a big physical striker like Pogrebnyak (who would be cheap from Stuttgart) or Ibisevic from Hoffenheim. If he's looking outside of Germany he could do worse than signing Aliyev and Milevsky (both at Dinamo Kiev).
He needs to sign German or German-based players, with them you get born winners and consummate professionals. The Germans would also add a bit of much needed steel to the rather flakey Arsenal back line.