For these reasons, I object to it being used, and much prefer the existing 2 column proposal.
=== Dolske (2) ===
I had a few more ideas on streamlining things, and did a [http://people.mozilla.com/~dolske/bugzilla/ rough mockup] to see how well they work. It needs fine-tuning, ignore any fixable rough edges.
* The outlines and icons of form controls add a *lot* of visual complexity to the page. The mockup replaces almost all the HTML controls with just plain text (but you can reactivate the controls by clicking "edit"). This really improves readability, but the obvious cost is having to click "edit" to update fields is annoying. This needs improved.
** A subset of commonly used control could be active by default, or BZ could be smart about enabling controls based on the bug state (eg, an UNCONFIRMED bug is probably going to have it's state changes, Firefox/General bugs probably need a new component set).
** A single edit link per section/page, or state via flag in the URL/cookie. Mitigates problem somewhat.
** Can CSS styling of the controls make them more muted?
** At the very least, this makes a cleaner page for viewing bugs when you're not logged in (or don't have an account). If you can't edit something, we shouldn't show a control for it.
* The top part of the bug is using CSS3(ish) columns, so you will see 2 or 3 columns depending on how wide the browser is. Or, uhh, 1 column for narrow windows. And browsers that don't support -moz-column-width. There's not much control over where a column starts, so tweaking a design to work with different column counts is tricky (the mockup just happens to look fairly reasonable). Perhaps there are JS/DOM tricks that could help? I consider this a failed experiment as-is.
* The CC list is hidden again (ala mconner's mockup). While some don't like this, it just doesn't seem that much worse than the current design, which only shows 4 names in a scrolling list. Maybe overlaying the list when you hover over the field (like a giant tooltip) would be useful? That would allow you to easily see all the CCs at once.
* Some space is saved by combining fields onto the same line. For example, OS + Hardware, Product + Component, etc.
Other thoughts:
* The big radio list at the bottom of the page (right above the "Commit" button) really needs to be simplified, or even eliminated. Most of these actions could be some from the controls at the top of the page, with better design.
* The "Depends On" and "Blocks" fields should be clipped if they're really long (with a mechanism to show them all if desired). "Depends on: 99 bugs (2 open, 97 resolved)" seems more useful than a giant block of numbers.
* The linked labels (like Status) shouldn't be overloaded for help. (If they should, why not all of them?). Having a link for help somewhere on the page (header?) would be a good idea. Although "Keywords" probably needs a small link for allowed words (or conversion to a select box).
* Bugzilla should lend a hand when you're filling out a field with a name (assigned to, qa contact, flags). "Default" is probably needed as a minimum, although a longer list of people appropriate for the task would be nice.
* Is the Hardware field really even useful? It seems like OS alone should suffice, with a comment explaining any particular hardware dependency.
* The yellow header bar linking to mozilla.org seems completely useless. Maybe make it a footer, or just delete it entirely?