Many of these comments place H1B's as a target of their wrath. I have never experienced this to be the case, but I also don't like to go around blaming immigrants for problems I created for myself. I have seen (and benefited from!) a job posting being specifically opened for me, exactly, to fulfill some corporate requirements.
I think the people that bash H1B's and internal posts are on to something. These super specific requirements are to reject someone (Americans & external applications described above.) I disagree that this tends to be on the basis of citizenship, but I'm sure that does happen. What I saw was super specific requirements used for was a way to reject someone you didn't really want to work with, because they were basically unpleasant, but probably technically competent. I imagine that this actually classification fits into a large portion of the slashdot community, with the negativity I read in the majority of comments on pretty much every post. At the places I worked as an employee, it was a lot "easier" (in terms of not getting sued, and rejecting someone) to possibly allow them to interview if they seemed technical competent, and then reject them based on an unrealistic, wish-list of skills, as opposed to rejecting them because they kept complaining, or for some other (politically incorrect/illegal/lawsuit-prone) reason.
It is very, very, VERY difficult to fire someone in the United States. Even in "right to work" states, employers have a lot of fear about lawsuits and other employment related issues. I took the independent contractor route, and it is BY FAR easier for me to score clients than it any of the multi-phase, tons of telephone, and in-person, interviews required to be an employee. Wouldn't you want to be extra careful on the hiring side, if the firing side is going to be difficult? As a contractor, if someone doesn't like me, I'm gone in an instant! Between this, and being able to ramp-up / ramp-down my time, it's a way more flexible agreement than permanent employment, and I find marketing myself as a contractor to be much more pleasant than the four or five times I marketed myself as a technical employee.
I hope you find this useful, entertaining, and not too offensive.
-Brian J. Stinar-