Peter Hill-Wood says that Henry used the Wenger situation as an 'excuse.'
When Thierry Henry trots out Wenger's unsettled future at Arsenal as a reason for leaving, he is using psychology 101, using and blaming extenuating circumstances to lay a smokescreen on what could be perceived as a less than honorable motive. Rationalization and projection or R&P. Because he felt unsettled, he projected his anxieties onto the club. That is when you start looking for an escape clause. But you do it in a way that saves face. The reasons given seem to suggest that Arsenal drove him away. But we see R&P at work everyday. From justifying endless wars to Henry's reasons for leaving. The bottomline is this.
He wanted to play for Barcelona because that is where the big names are. They are in the galacticos building stage and Henry gets a huge ego boost when he goes to the locker room and finds that his neighbours are Deco, Messi, Eto'o, Ronaldinho, Grosso. And now Chivu and Yaya Toure. At Arsenal it was Adebayor, Flamini, Hleb, and Van Persie. Not players at the tip of the tongue when you want to consider a World first XI.
Just a note. I think Didier Drogba if he decides to move on will have handled this far better. He has made his intentions clear. He wants to play for the Liga or the Serie which he thinks will provide a different sort of challenge. When he leaves it won't be this agonizing, read the tea leaves way, that Henry subjected Arsenal to. Drogba might be a flopper but being the Ivory Coast captain of a country torn with civil strife has imbued him with a sense of destiny. He can afford to be crystal clear.
As for Wenger he will stay. He has changed the face of Arsenal with his brand of soccer and put into place a business model that is a counterpoint to 'we await a new owner with loads of money or woe is us.' OK. We need to shell out money for a Henry replacement but I have a feeling Wenger is doing his homework on that one.