If you don't already have a alpha/beta/gamma of your web application live, I think a prototype of an interesting web project would help raise your application's chances. That being said, interesting ideas are cheap - my goal is to put the time/effort/energe to mold one of my ideas into a live proof-of-concept/prototype by the application deadline... in basically one month's time.. in Ruby on Rails (which I've just started learning).

The fact that GMail started out from humble beginnings ("I wrote the first version of Gmail in one day. It was not very impressive. All I did was stuff my own email into the Google Groups (Usenet) indexing engine." - http://tinyurl.com/2zs4pe) is inspiring.