early 2011 MacBook Pros that promises to "improve graphics stability and external display compatibility." That sounds like it may actually fix both the freezing issue we reported on earlier today and the flickering issue that's been plaguing Thunderbolt-equipped MacBook Pros since day one, though we've yet to confirm either ourselves. Let us know how things work out for you in comments.
Update: Early indications are that it does indeed fix both the freezing and flickering issues. We'll let you know if we find anything else.
[Thanks to everyone who sent this in]