Some of my avid blog readers were a bit confused when adding comments - it's not obvious how to format urls, images, etc.
So - the first step was to add a live preview! It should at least show you what your comment will look like before you post it.
The next step will be to add some buttons to insert the codes for you - around any selection. For now though, the supported UBB codes are:
[b][/b] - bold, [i][/i] - italics, [u][/u] - underline
[list][/list] - for lists, which must surround [*][*/] list items
[center][/center] - to center align
[url=][/url] or [url][/url] - hyperlinks
[img][/img] - to link images
[code][/code] - for preformatted source code
[quote][/quote] - for quotations
I haven't tried all of these, so feedback is welcome (Will).