How does the new Spotlight know whether or not you're using it as a quick app launcher without communicating back to the mothership? I would have thought that it would send every query and then display the result or not depending on what comes back. I don't see how you could reasonably do it otherwise, unless you want to block internet searches for any term that matches an app name.
From using it, when you start typing, it immediately shows the top local hit, but it doesn't expand to show results until you've stopped typing for a noticeable period of time. Note that if you type a long query slowly, you'll never see results, even though you've been typing for a while.
Based on the consistency of the delay, I assumed it was doing the quick local search for the top hit, and then deferring the more expensive searches (including internet-enabled searches) until it's decided that it's time to show the results window. So I tested it, sniffing http traffic, and while I didn't pinpoint which particular queries are sent by Spotlight, there was reliably a burst of HTTP traffic right before the results window was shown every time, and no noticeable HTTP traffic before then. This suggests that my assumption is correct, that it's not doing the internet-enabled search until it believes that the user is done typing.
Based on this, if you type your search and hit return immediately, then it won't have sent your query anywhere.
