Software Development - Project Managers

This post is a rant. If you don't like a rant, I suggest skipping this.

I am intruiged at the fact that IT Project Managers will allow untested software to be released to the world.

I am beginning to feel that in the corporate world, software developers are the most unappreciated people and also I am having the inkling that project managers are not operating at effective levels.

According to wikipedia, project management is the discipline of planning, organizing, and managing resources to bring about the successful completion of specific project goals and objectives.

And if a software developer is a resource to the project, my argument is, does this mean that the resource is not being managed properly? Does this than equate to the fact that the project manager is not performing their role to a sufficient and acceptable level?

Yes, sufficient and acceptable is subjective, however, when a Software Development project is over cost, delivered past the deliverable date, who is to blame?
From experience, the blame falls squarely at the feet of the developer. The word around the water cooler is, "so and so is doing a bad job, he's not delivering the project". However, my question is, is the developer solely to be blamed for the ludicrious time-line and deliverable date set by the Project Manager?

My question than is, who set the time-line?

Who spoke to the client and made the promise to the client that at a certain date, the project is going to be delivered?

Do they understand the intricacies of software development?

Was testing done prior to release?

Does the project manager understand that the computer is nothing but a dumb terminal that has to be told in specific fine minute details to perform a certain task?