I'm one of the few people who visits here -- not as often as I used to -- who doesn't think clipping is evil.
I saw the article quoted above elsewhere, and I want to address the paragraph getting down on someone for taking the bird to a groomer frequently, citing it as evidence that that person doesn't understand the nature of the bird. I think that's somewhat distorted. While in nature birds molt in an orderly fashion, it's quite common for pets kept indoors to molt erratically or continuously and a trim does need maintenance. Perhaps not monthly, but not once a year either. Now, it's ideal if your bird is trained to allow you to trim a feather here or there without drama, but that's not really the point that was being made.
I think it very much depends on the bird, the people, the environment and the circumstances. Clipping doesn't need to be severe, and feathers do grow back. A light trim limits range and speed. Even quite a severe trim won't guarantee a loss due to a bird getting outside. IMO it's about the balance of safety and freedom, and I wish there were more hard data to illuminate the pros and cons than there currently exits. Most of the arguments made are essentially emotional, either way.
At any rate, it's always possible to see how the birds are settling in and then decide.