This class involved bantering about nothing and and absolutely everything at the same time. It was a small class (usually 3 unique friends that I had just met). And the format was twice a week/discussion. I think it was called: Late-night/post party/stupid drunk/socio-political seminar 101. Take it. Seriously.
That's exactly why I was initially worried 1) because most tech-ventures have low barriers of entry (due to low over-heard costs) 2) generally speaking, the expertise required to implement a novel idea is almost rather trivial because programming is a commodity skill.
Maybe not--but the article is written in a way to minimize the importance of a good idea. Read below:
"In particular, you don't need a brilliant idea to start a startup around. The way a startup makes money is to offer people better technology than they have now. But what people have now is often so bad that it doesn't take brilliance to do better.
Google's plan, for example, was simply to create a search site that didn't suck. They had three new ideas: index more of the Web, use links to rank search results, and have clean, simple web pages with unintrusive keyword-based ads. Above all, they were determined to make a site that was good to use. No doubt there are great technical tricks within Google, but the overall plan was straightforward. And while they probably have bigger ambitions now, this alone brings them a billion dollars a year." (How to Start a Startup)
Sure, search engines sucked (algorithm-wise) before Google but the concept/idea of a technology to aggregate links by relevance, was pretty critical to Google's existence, IMHO.
That's true, no idea by itself is sufficient to becoming successful unless there is solid execution/implementation. However, in the case of startups that are "inventing" a product instead of making something existing better the initial idea becomes the "moneymaker". Startups applying for YCombinator to improve on an existing product (social networking, social news, finance softwares) don't have to worry about giving away an idea that they have been brainstorming for months. They primarily are banking on the fact that their approach is solid and the engineering of the product is high quality (no easy task either).
The idea is a very necessary factor, but yes not by itself sufficient. The Paul Graham article "How to Start a Startup" assumes that a startup is only developing something to improve on an existing idea/technology.
A startup inventing a product would be taking a huge leap of faith by believing that a power broker like Y Combinator would not be tempted to (in the event they came across an idea that they felt was revolutionary) to not farm out the engineering/business dev to seasoned developers; especially if they lacked faith in the approach/abilities of the founders. After all the process of execution/development is pretty much a commodity task.