Painter played pretty good in his last pre-season start if I remember correctly (yeah, he was freaking awful in the first couple). It made sense for them to bring in Collins, but they handed him the reins too quickly.
HIndsight is 20/20, but I really thought at the time (when they signed Collins) that they should have stuck with Painter to be the starter. Why bring in a journeyman QB at the end of preseason to lead your team, especially when Painter was showing signs of progress? Collins is a savy vet, but he's no Favre. It was a panic move and it failed miserably.
I'm with gilthorp...it's too early to say Painter can't get it done, but will the Colts give him a real chance? The season is just about lost and they should let this guy play some unless he's totally ineffective (see McCown/JAX).