First of all: I am very happy with the new theme mechanism and freedom of structure.
I am currently slapping together my first theme release - which inspired me to the following thoughts.
Here are some suggestion - for future versions, but also to all those great theme developers out there:
* currently WP reads it's themes informations from the CSS - which is good, but could be done better? Maybe each theme should contain a wp-readme(.hmtl) which WP displays/contains infos instead of the CSS header - since not everyone expects informations there.
* the displayed readme/info should inlcude at least the following bits: name of the theme, home URL, developer name, contact, version/date, file list, tested browsers, needed plugins, special instructions.
* the Presentation section in the admin panel should include links to the apropriate sections in the codex, to make it easier for beginner to find more background informations on using and hacking stuff.
* maybe every theme should include a small preview snapshot like theme-preview.jpg, which can be seen in presentation panel as well?
* Designers should include in this readme a small rundown which file does what - especially when people use several files to call each other.
* I highly recommend some serious commenting in the theme files as well - it saves a lot of 'aftersales' support and helps newbeeeees to understand what your theme is doing.
* an update mechanism would be extremly cool a la FireFox - but I guess we want this for plugins as well? ;-)
Just some thoughts ... thanks!