@Eric Mann -
I can see some of the arguments. A lot of the debate is descending into “I don’t like it, so it’s a bad idea.” That, and it’s beginning to get very charged emotionally, which is always a bad sign for what began as a rational discussion.

That said, it does appear that this change has been implemented with an accessibility blind spot (pun intended). Kevin John Gallagher makes a great point. Accessibility may be an edge case, but as WordPress becomes more prominent as both a CMS and as a blogging platform, it is an edge case that can't and shouldn't be dismissed simply because it is an edge case.

And that said, Jane Wells knows what she's doing WRT usability, and I trust that she and the UX group will address this issue.

As for the "I just don't like it" crowd: if a Plugin hasn't already been released, I'm sure one will be released sooner rather than later.

(I always roll with the admin menu collapsed, anyway, so the loss of dropdown menus is no loss to me whatsoever.)