Google has confirmed that they are indeed testing a form of infinite scroll web search results as like in Images.
As you can see in the blow video, Google replaced the pagination feature from the bottom, where it says, “Gooooogle” and put a link that reads “show more results”. Clicking on that will load an additional set of search results directly below the first set of results.
A Google spokesperson confirmed this test saying, “Google is constantly experimenting with new features.” Google has previously denied an infinite scroll test in November of last year, blaming it on a Chrome extension. But this new test, seems to be the real thing.
Will this last, I am not sure but we do know Google has infinite scroll on image search. Here is a picture: