Nobody is complaining about the idea behind the marketing. I think it's a great idea that helps promote both the indies and Portal 2 at the same time. However, the timing of this part of the campaign was poorly thought out. Starting it this close to release means that Portal 2 will only be unlocked a day early and on a workday too. If they had started this last weekend, it would have potentially been unlocked much earlier. Therefore, more people would have been compelled to buy and/or play the indie games involved because the reward would have been more significant.
Again, not a criticism of the idea. Just a criticism of its implementation.