[mikhaill]

The issue is that when you use Facebook connect and get the user's email it returns the email originally used to sign up for facebook. Since people signed up years ago, many no longer have that as an active address, which leads to the poor email quality.

[makomk]

Wow - I expect most Facebook users have invalid e-mail addresses if that's the case. Originally, you could only sign up with a college or university e-mail address, and pretty much all of those addresses are now dead because people graduated or left.