great ideas xavier:

• let's definitely add "not yet converted to v3.1" to templates
• i definitely see a place for ids in the templates - my primary concern is that in some cases i expect that we will be using user-generated text for "unique" form items (specifically, custom profile fields) and fear conflicts. my solution (you may have a better one) - has been to use "unique" class names to target individual elements, which minimizes the potential risk. i have not run into any situations where an id was required and a unique class name could not be used, but maybe i'm missing something?
• zebra striping: this may be a matter of stylistic preference, but i prefer to keep the classes in the html - in my experience rendering speed is improved (especially for extra long tables) and we don't see any other performance gain by doing the striping in jquery (except for developer convenience ;)
• Dave and i discussed the table-layout issue on complex forms - there is certainly room for debate. My goal for moving to divs is not so much to become strictly semantically accurate, but rather to empower developers to make style choices more easily. (for example, currently it takes changes in .tpl files to move labels from one side of an input field to another - if we'd like to accommodate right to left languages using CiviCRM, it behooves us to turn this into a simple CSS change...)
• i totally agree on microformats, as long as Advisory Group/CiviCRM agrees - if so, let's try to include this into the markup recommendations with 3.1. - issues i see related to this are that the jquery-ui date picker does not use hcalendar formats, and there may be other cases in which other choices we've made will make using microformats difficult - would this be something you would be willing to look into?