Yes, that's exactly it. Local UI (initially in the browser, but could be on a rich-client or mobile app) but all compute is in the cloud.
The difference from existing thin-client models is that it's a single stack: When you write a program, you write the UI code as if on a local computer. E.g., you just call MessageBox("Hi, there") and the platform is responsible for remoting that as appropriate.
"A super massive global mainframe" is the correct analogy, but instead of a text-mode VT100 terminal, you get a full remote GUI (more like X Windows).
The difference from existing thin-client models is that it's a single stack: When you write a program, you write the UI code as if on a local computer. E.g., you just call MessageBox("Hi, there") and the platform is responsible for remoting that as appropriate.
"A super massive global mainframe" is the correct analogy, but instead of a text-mode VT100 terminal, you get a full remote GUI (more like X Windows).