[ricree]

I just checked my download page, and the new additions are showing up even though I bought several days ago.

According to the front page, the new ones are for people that paid more than the average. If you have bastion but not the new three, then perhaps they were based on the average when added to the bundle. That's likely gone up, so if you paid less than the current average but more than the average when you paid you might not have gotten them.

[dlevine]

You get the new games if you paid more than the average when you originally purchased. I paid $7, which was a bit more the average when I originally bought the bundle (day 1), and the new games show up in my account.

[Fargren]

No. You get them if you paid any amount before they were added. I had payed well below average (buying foreign currency is currently very hard in my country) and I got the games added.

Also, from a recent interview with the guys from the bundle[1]:

RPS: Is there any temptation to have it be so you only get the extra games if you up your payment to above the average?

Richard Esguerra: No, I don’t think so. That’s not been discussed as an option, but it has been communicated internally that that would be gross. It feels like a bait and switch, you get penalised for buying earlier. That doesn’t make any sense for customers. If there’s anything that we’re super-rabid about, it’s about gamers – it’s about the gamers’ experience, about how awesome the experience of participating in a bundle is. Getting to pay what you want, getting to choose where the money goes. We want all that to be as awesome as possible, so we really try to avoid experiences where people will feel like, “Oh, why did I buy this when I did.”

[1]http://www.rockpapershotgun.com/2012/06/07/humble-bundle-v-a...