DogFooding has been started, from RC1. Surprisingly (or perhaps because of the nearly one month of preparation time spent) it is quite stable.
However, some trivial things have been found. I will fix it by the rc2, and keep using this.
Through rewriting into modules, I found a few issues and more potential issues. If Heinrich were here, he would say that there must have been a serious problem. Quite good opportunities I have got.