For OS X, I don't know about defrag at all, but I do know that Apple has been late to add TRIM support. Right now (as of 10.10.4) I believe you still have to run a shell command to enable it, or did as of January this year, and more complete support is expected with El Capitan.
Windows 7 (and later) had TRIM supported added via Windows Update back in 2010, but it was disabled by default in most cases (the bios must be using AHCI mode, which was less common then). There have been updates since both from Windows and OEM manufacturers that make it much more likely to be enabled today. Generally, Windows does the right thing here. Additionally, Windows is smart enough to know the difference between an SSD and an HDD and won't try to background-defrag SSDs very much (see here: http://www.hanselman.com/blog/...)
I don't know of any **mature** file system designs that are explicitly optimized for SSDs from day 1, but I'll be surprised if one isn't in development.
Now you pay Spotify $10/month for unlimited access to the entire album. To the entirety of the artist's catalogue. To the entirety of all the included artists' catalogues.
This is obviously and trivially less money than any one of those artists would make previously from you if you liked their music.
What makes you so sure there's less money here?
I remember that we used to pay about $10 per album (with the exception of certain top 40 new releases that cost twice as much that I never bought), and I used to buy about 1 album per month. If everyone who did that switched to Spotify for the entirety of their music consumption, that's exactly the same revenue going into the system as before.
It's even better now. Under the old system, if you liked an artists music you bought it once, and that was the end of the transaction. Especially for new artists with only one or two albums, that's tough. Who goes out and buys an artists' entire back catalog, anyway? Under the new system, if you like the artists music they can keep getting paid as long as you keep listening to it.
Is a computer language with goto's totally Wirth-less?