I doubt they will raise $600 million from this bundle, so far they have managed to raise $3.7 million, out of which some will go to charity and some will go to HumbleBundle itself. Make no mistake, this is a huge amount for humble bundle, but it will not get them out of the woods. Only good products and smart management will do that. And neither should it. Fans are not here to make up for the management's **** up. If the bundle sales prevent bankruptcy, then it will have served its purpose.
As for other companies following this model, the THQ bundle has been controversial. While many people see this as a possible answer to piracy, many people have also accused Humble Bundle of selling out to big publishers. The Humble Indie Bundle has always offered DRM free, platform independent and indie games, none of which apply in this case. Me, I love it. With this bundle I have convinced two friends to "buy" the games instead of pirating them, which is big win for me.