His attitude, leadership, and performances have been questionable, and to some people he is like a poison in the Arsenal squad.
I suppose he is not the best captain the club has ever had, but it is perhaps a more difficult team to captain than some others.
Vieira was captain of a team that didn't need captaining with players like Campbell, Ljungberg, and Gilberto having experience of the job themselves while other senior players like Pires and Henry were hardly the types that needed keeping in line.
Vieira still managed a widely publicised physical confrontation with Lauren though!
This young team needs more considered thought to get the best out of them. In some ways Gallas takes the job of captain too seriously and his comments will not help him. However, stripping him of the captaincy now, as much of the press are urging, will not serve the cause of harmony within the team well.
Gallas has, more often than not, done his job reasonably well. It is when the going gets tough that he fails to set the example that is expected of him.
I will not delve into the over-publicised incident at St. Andrews last season. He shouldn't have done what he did. What the incident did however, was give everybody a glimpse of what sort of captain and leader he was.
His latest outbursts, as pointed out by our good friend Alex Dimond, will not go down favorably. As a captain, a lot of issues will depend on how he handles it and going public is a definite no-no.
He has clearly shown that he does not want the responsibility that goes with being a club captain.
His football ability has never been in doubt as his career across London with Chelsea proves. He has never quite been able to recapture the form he enjoyed at Stamford Bridge, though.
In his defence, he has managed to produce some critically important goals for his team like the winner against Chelsea and the late equaliser against United.
On the other hand, Ashley Cole is playing his best football for Chelsea this season. He is by no means a saint and his attitude is arguably worse than Gallas', but his performances are slowly but surely winning his critics back again.
His Chelsea career got off a rather weak start with a series of bad, nervy performances. He looked weak, unsure, and lacked confidence. The fact that he was frequently substituted or left on the bench in favour of his England teammate Wayne Bridge proved that.
He did briefly get back his form of old, but his much publicised off-field personal problems seemed to have to got to him and Chelsea did not hesitate to drop him again.
His attitude as a pro footballer is one of the worst I have seen in football. The way he turned his back on Mike Riley in that 4-4 draw at Spurs was disturbing, especially as it was just days after the "Respect Referees Campaign" was launched.
This season however, he was come on leaps and bounds. His improvement and new dedication is there for all to see.
A change of manager seems to have done wonders for his confidence and playing style. Playing under Mourinho and Grant, he was restricted to just defending when he has so much more to his game than that.
Big Phil likes to give his wing back a free licence to roam forward and join every attack, and Cole is relishing his new lease of life.
Now, back to the question. Between Chelsea and Arsenal who got the better end of the deal?
Chelsea, without a shadow of a doubt!
Letting Gallas go and paying an extra £5m for Ashley Cole, who was widely regarded as the best left-back in the world at the time, was a stroke of genius.