My sister just told me about one of her major pet peeves with Google and I thought it would make a good discussion topic. It might help if I explain how she uses Google so that you can picture the results.
A) She visits google.com and types in her keywords in hopes of finding what she wants.
B) She quickly glances at the instant results being displayed.
C) Happy at what she sees she finishes her typing with an instinctive tap on the return key, and that's when she pounds the keyboard.
Depending on what you're searching for the instant results you see when you're done entering your search terms are NOT the same results you'll see if you hit enter. They change. My sister says it drives her nuts when the result she WANTED to look at vanishes.
I explained to her how to turn off Google instant and she says that it never stays off, especially at work.
I played with Google instant a little bit and she's right, simply hitting return changes the order of rank on many serps. Why?