Only on a site like HackerNews. Everyone I've shown 99D to thinks the idea is great (as do I).
I don't understand why designers care one lick what other designers are doing for work. I don't begrudge people for using AirBnB instead of a hotel, or using Uber instead of a normal taxi.
I guess some people feel it is taking advantage of the less fortunate, but everyone knows how it works going in; for this reason I can't quite share the same disgust.
Now, the logos may not be as good as done by a true design company, BUT, unless you are a big B2C brand, nobody cares what your logo is like.
However, if you're having a critical piece of software written for your business, then clearly you need to care about that - outsourcing may or may not be the best option, just as using 99designs for a logo may or may not be the best option.