Quiddity: A scene extremely similar to this happens in the absolutely horrific OVA Eiken(arguably the worst anime ever IMHO). Our weak willed male main character accidently topples over a quiet, mysterious girl, and finds his hands on her breasts. The big difference being that the girl's boobs in Eiken are about 50 times larger than Rei's. Whether this is a homage to Eva or not I can't say, after all this type of scene is quite a cliche. I'm quite surprised a high quality show like Eva stooped so low.
thewayneiac: Rei's reaction, or rather her lack of reaction is important character develpoment. This is not just another fan service scene.
