Do webmasters share a similar sentiment on expectation of Facebook's performance?
Yes. There is a slowly growing backlash among many users due to spam-type issues. It is much like what we saw in the early days of email. I would add that more and more businesses are putting a very low number on what they are willing to invest in managing FB. There is a growing unease about building an audience in a network controlled by someone else (a la Google, only worse).