As part of Microsoft's "secure by default" design philosophy, IE7 will block encrypted web sessions to sites with problematic (untrusted, revoked or expired) digitial certificates.
Along with their increase in security, I hope Redmond has increased their attention to detail. Anyone remember certain lapses in ownership of certain domains in the recent past? There's only so many honest people, like Steve Cox or Michael Chaney, out there. There's a lot more dishonest people out there looking to create mischief or earn a quick buck.
My offer to Mr. Gates (to host cron'd reminders for domain renewal) still stands if he wants it. (heh)