It's not really necessary to segment by sector; you can simply have one pool of visas. The efficiency implications actually work better that way - a "shortage" of workers in a non-productive economic sector isn't really a shortage.

If you think an industry has non-economic benefits or positive externalities the correct response is to help them capture that directly, not futz with the labor market to give them an implicit subsidy.

I'm thinking not of industry, but of academia and research. It's not going to work to just give blanket subsidies (like say, 20k to all Postdoc researchers) - you need a system that allows in foreign researchers, and my point is it's hard to differentiate academic research from industry research. Also, everything discussed is "futzing" with the labor market - it's not like setting up a government run auction is some sort of pure free market.

I tend to agree that there is no need to control for sector. In fact, I'd say one reason that a "shortage" exists in certain fields (such as software development and especially science) is that the people capable of going into these fields have better options elsewhere. A lot of people are surprised to learn that in San Francisco (ground zero for the tech "labor shortage"), the median salary for application developers is only a whisker higher than for dental hygienists and considerably less than for registered nurses[1]. That's fine by me, but if H1Bs for nurses come in at a higher level than for software developers, why wouldn't we let in all the nurses in first, and the allocate the remaining spots to the software developers and dental hygienists? What's wrong with that?

[1] http://money.usnews.com/careers/best-jobs/rankings/the-100-b..., drill down to salary details which will show salary by region. This is a roundup of BLS data. You can query that directly at the BLS site, with more than just the median. Interestingly, software developers do earn more than nurses at the 90%ile for both fields, but only by a small margin. At all lower percentiles, registered nurses out earn the equivalent percentile for software developers.

Every time I mention this, someone points out, reasonably enough, that nurses are hard working, smart, valuable people. I think they may be worried that I am implying that it is unfair that nurses make more than software developers. I assure you I have no problem whatsoever with higher salaries for nurses, I think they deserve them! I just see absolutely no reason to help corporations pay a lower value type of worker (software developer) the lower wages they deserve.

There's also a data problem - anyone is allowed to call him or herself a software developer (or even engineer), whereas there are controls on who is allowed the title "registered nurse." Keep in mind, though, higher paid nurse specialists and physicians are not in those numbers either, nor are the lower salaries for nurse orderlies. So I do acknowledge the data is not as simple as I have presented it. What I do think this suggests is that trying to set up separate categories doesn't make much sense (imagine if you could set the H1B minimum pay for a radiologies by averaging it in with the nurse orderly category).

If H1Bs end up going to finance and health care, well, fine. That's a good sign that there isn't a shortage of high tech workers in the first place. If google and netflix want a visa for a $275k a year worker, they'll get one. If someone wants to pay someone $60k a year to update payroll information with .NET and SQL Server and the visas go to better paid nurses and financial analysts, how on earth is that a problem?