For most applications for a little while I suspect the benefit will be in having an OS that can schedule processes onto more processors. That's nice and will improve the experience for people. OS designers can probably use more daemons as a result to do other fun things. The browser, for its part as some slow, broken version of an operating system, gets to run each page as a process and helps that experience some too (which is already happening with each tab is a process).
I don't think your typical application will have to take advantage of all 200 cores in an explicit way. The use of dynamic languages on the desktop signifies that developers have been willing to throw away performance for development time for a while now. Why is that suddenly going to change, especially with the more difficult concurrent landscape before us?