Each competitor I see certainly nudges the bar higher, but it's only a nudge. Ultimately, we're all building web applications. They're just code, markup and javascript. The great thing about the web is that the entry requirements are very low and your competitors, no matter how strong, can never raise those requirements.
FWIW, my startup is testled.com. Our competitors are people like userfly.com, clicktale.com etc.
You have to ask yourself, why am I being discouraged by this competitor? Usually it's because you're afraid that whatever you had in mind has already been done. And that they're already doing it better than you'll ever can. In that case, you should take your discouragement as a real signal.
Take care of the tougher aspects asap, you'll have to go through them anyway.
Facebook started off nicely despite having Myspace and a bunch of other social networks.
Anyone have any experience with this?