I've had my rejection letter as well and I was actually surprised how human and respectful was this letter. They're very good at marketing, it's like breaking up: it's not you, it's us! ;)
I think it's obvious that this rejection letter should not put a stop to your projects but rather keep improving them, that's what I'm gonna do.
I already applied to techstars and I will apply again at Y combinator. Next time I'll be ready!
I'm looking for a co-founder in order to launch a new mobile advertising platform for hyperlocalized marketing.
You can support my application at TechStars at the following url: http://www.f6s.com/geome#main/ajax-summary
I'm still at an early stage but if you're interested, PM me and I'll explain you what this is about.
You can also follow me on twitter: @Nicrogo
Many thx!!