At first I didn't like it, but I've eventually started to really like this in OSX. Having a ridiculous amount of RAM to "waste" may have helped change my mind. My only gripe is that I wish it were a per application setting.
Some apps, like my browser, mail program, the terminal, Emacs, ... I love having start quickly, even if it's because they were just in the background before.
Other stuff, like Preview, I don't use often enough to care about the load time, and I would probably configure it to exit when the last window closed.
>> Other stuff, like Preview, I don't use often enough to care about the load time, and I would probably configure it to exit when the last window closed.
Under Lion, that is (sort of) what Preview and TextExit do. When you close all open documents in Preview and then switch away from the app, the app will terminate.
For Emacs, you should consider using Emacsclient and server. That way it's always on in the background, takes a fraction of a second to open a new window and shares state between all the different windows. Additionally, it lets you configure programs that use an external editor, like Git, to just open a new buffer in your current Emacs session, which is very convenient.
Some apps, like my browser, mail program, the terminal, Emacs, ... I love having start quickly, even if it's because they were just in the background before.
Other stuff, like Preview, I don't use often enough to care about the load time, and I would probably configure it to exit when the last window closed.