I am one of those people that loves the AJAX search. I know it's generally hated around here but I think getting the suggested results as you type in your search is one of the best search features Google has implemented.

For example, let's say I found some new framework for a new language I haven't worked with. I can easily find competing frameworks by typing in something like '[framework name] vs' and Google will will suggest the most commonly compared frameworks. I think it's very useful when you don't know exactly what you are searching for. Yes, I know it has some usability issues but in my opinion the pros outweigh the cons.