One thing I didn’t write about that much in my latest book is the phenomenon that allows a new product to cross the chasm and reach the vast majority that are so busy ignoring you.

It’s the hit effect.

When all the early adopters at radio stations start playing a Norah Jones song, it becomes a hit. Billboard magazine charts it. It spreads. First to radio stations that only play what’s on the list, then to consumers who only buy what’s on the list.

When all the early adopters in silicon valley start carrying a Blackberry pager, it becomes a hit. They feature it at Fry’s. It spreads. First to the friends of the geeks, then to people who buy what nerds buy.

The middle of the market wants to be safe. They want to buy what others are buying, read what others are reading. And scorekeepers–like bestseller lists and cash register displays–are the barometer they use to determine whether a new idea is safe yet.

Tivo’s challenge, for example, is that Tivo is essentially a private device. There’s no obvious list it could be on. No retailer it can dominate. As a result, it takes far longer for it to jump over to the middle of the market.

One lesson here is to try to create products that have obvious lists. The second is to figure out how to work with early adopters in a focused, coordinated way to get on that list.