It's not really a mystery.

I think a few things they didn't mention are:

- Graphics. The reason Darwinia and Braid and World of Goo get coverage and The Spirit Engine etc. do not is probably primarily graphics. That might be shallow, but it's true, nobody wants to review a game that looks like it was made of clip-art, no matter how good the gameplay is.

- Previews: games that come out of nowhere aren't as appealing to review as games which have been highly anticipated and have a lot of hype prior to release. For about three years we kept saying new previews of Braid (and to a lesser extent games like Aquaria, The Underside, etc.). I actually think previews matter far more than reviews in terms of getting exposure. You know a game get a lot of reviews when you see it being previewed every few months or so.

- Reputation. You're more likely to get a game reviewed if you've made a lot of previous games that also got reviewed by the same site / person. First-games have a much harder time getting reviewed or previewed, since nobody has heard of the author before. A new cactus game, no matter how bad or good it is, will probably be downloaded thousands of times on its release, just based on his reputation.

So, I guess, if you want your indie games to get good press coverage, give them good graphics, submit them for previews, and release a lot of games.

Paul hit the nail on the head.