The best published records are now down around something like 10^7 cm^-2, or something like that, I don't recall off the top of my head. It really depends what you're trying to make. For cheap LEDs on sapphire, there are a lot of threads. That's all they had back then, and there are still a LOT of devices made that way. For high-performance stuff, like lasers, threads are a bigger issue, so they do a lot more work in that area.
So basically they're still there, and devices are still getting better all the time.
He was awarded a Doctor of Engineering degree from the University of Tokushima in 1994. He left Nichia Corporation in 1999 and took a position as a professor of engineering at the University of California, Santa Barbara.
In 2001, Nakamura sued his former employer Nichia over his bonus for the discovery, which was originally ¥20,000 (~US$180).
Although Nakamura originally won an appeal for ¥20 billion (~US$180 million), Nichia appealed the award and the parties settled in 2005 for ¥840 million (~US$9 million), at the time the largest bonus ever paid by a Japanese company.
I don't know. At the time he discovered the blue laser diode, he was working for Nichia. From the story I red the "small" company took a big risk to allow him to continue the research about the diodes without any insurance of discovery or mayor cashflow.
Also when he went to USA in 1999, he must learnt some of the American suing practice.
Well without him we are still playing with red/green lasers.