I came across this course through some friends at the London Hackspace - but it took me over a year to get around to starting.
I'm a hardware engineer, so the first 5 chapters were fairly quick, and it was great to have code running on the computer within a few days.
However, I really enjoyed having my brain exercised in finding neat implementations of the pc and alu, and I have been thinking about working towards a real minimal implementation that runs on a FPGA - which will give me a proper reason to learn VHDL or Verilog - something that I missed out on when I studied in the early 1980s.
I'm looking forwards to the software 2nd half of the book - because these are relatively unfamiliar topics to me, and I expect to learn a great deal by working through the exercises - probably at a much slower pace.
Thanks to everyone who contributed to such a great self study course.