As a web professional, I understand the need for corporate ads and sponsorship but never at the expense of the user experience. And while product placement is common in movies and TV, it's typically downplayed (unless you're watching The Dead Zone) and when it's not it can generate a negative vibe to the viewer.
And I can only imagine what the typical Imagineer might think about the "bad show" this video clip and graphic ad present. It's not that the clip is itself annoying... it's just an AT&T commercial. But coming up automatically when the surround Flash site is trying to build an "aura of foreboding" is like seeing a commercial for Windex Glass Cleaner (tm) broadcast in Madam Leota's crystal ball before you even see her...
I can't say I'm surprised, BTW. The overload of ads and eye-distractions on the web seems to be a pandemic in the business world, and blockers seem the only truly effective way to fight back.
As for Busch, and their euphemistically-named "Worlds of Discovery" site, well... two words: Singularly unimpressed.