[wp-hackers] Shorthand: Appearance/switching themes?

[Lee Rickler]

Source:
http://wpdevel.wordpress.com/2012/01/05/dev-chat-notes-01042012/

"We agreed that 3.4′s “theme” would be, “Making it easier to make your site look how you want it to look.” Shorthand: Appearance/switching themes."

Can I simply ask - why?

Where I, personally, come from is the view of a developer building custom themes for clients. I believe that once I deliver a theme to a client the last thing I want is for them to be able to start adding new themes.
Kind of defeats my purpose.

Now, if I look at it from a non-developer POV I can still see issues with switching themes every 5 mins - layouts change to drastically/ the viewer gets confused/ bad for UX, UI etc

Obviously I am just a very small cog in a huge mega engine, but i'm struggling to see the end goal of this decision.
Should I just shut up and wait my turn?