From ArsTechnica:
UPDATE
In a response to Ars, Humble Bundle co-founder John Graham assured users the company will "never stop creating Humble Indie Bundles... and the other bundle types we've successfully launched this year. But we’re also eager to see if our pay-what-you-want plus charity model meshes with critically acclaimed AAA content as well."
Graham said the new THQ bundle did not represent a permanent departure from the company's indie roots, and that the company may even release a third indie bundle this year. "This year has also been a year of many experiments for us that fall outside the traditional Humble Indie Bundle framework," Graham told us. "We’re very excited to be able to offer the gaming community a massive sale with blockbuster content and raise money for charity at the same time. We will of course continue to support indies content as a core of our business."
Regarding the lack of Mac and Linux ports this time around, Graham said plainly that, "in the case of this promotion, it would not have been possible for us to deliver this blockbuster content via other means." But Graham also promised the Humble Bundle "will not cease in our quest to bring awesome content to Mac and Linux and Android," and pointed out that the Humble eBook Bundle contained the first digital publication of Neil Gaiman's graphic novel Signal to Noise.