[UPDATE: Part of this post (the first paragraph) was missing before and has been added; we just switched to a new version of Movable Type and I had some trouble getting it to take my post the first time and lost a paragraph somehow.]
Instapundit has an interview which has some interesting plots at the end, showing the number of engineering bachelor's degrees granted in the U.S. versus China and other Asian countries. Check it out. China passed us sometime in the mid-1980's and the growth rate in number of degrees granted is much higher. The trend is similar for graduate school, and also for the natural sciences generally, not just engineering.
I do know, however, that the relatively low number of doctoral degrees in science affects our own university system significantly. As a graduate student at a major U.S. research university, I used to joke that our department had a rule that postdoctoral researchers must be foreign, as none of the postdocs I knew during my time there were U.S. citizens. I'm now a postdoc at a different university and again, most (but not all) of the postdocs seem to be foreign, although many attended college and/or graduate school here. Generally, my sense is that the U.S. seems to award relatively few doctorates, and then many people leave academia after the doctoral level, leaving a lot of room for foreign postdocs. I think (based on looking at young professors I know) the discrepancy continues at the faculty level at universities.
Again, I'm not too sure what to make of all this. I don't have a fundamental problem with having lots of foreign postdocs and faculty members, but I wonder if it says something about our science education. I'll be interested in comments.