After the audio clip was revealed to be fake, I grew pretty cynical, pretty quickly. I didn't trust those websites at all, even though I wanted to believe.
The shame of it all though is the fact that any plans Bethesda may have had to do a genuine teaser are nixed, or at least they should be. There will always be people who fall for it again, whether genuine or not, but there's going to be a far greater number than before who will be skeptical. (Unless its made clear its genuine but.. without any mystery its not as fun).