We have tried a few approaches to address these, the typical way is to set a max word length in the backend but of course that will break URL's. As such, RC1 will probably have an auto-shorten hyperlink option if the user doesnt specify text in the url tag, or no URL tag at all. That is, they use this:
[url]http://compojoom.com/forum/7-wishlist/7093-forced-word-wrapping-and-chucnk-urls-dealing-with-long-urls[/url]
instead of
[url=http://compojoom.com/forum/7-wishlist/7093-forced-word-wrapping-and-chucnk-urls-dealing-with-long-urls]Click this link[/url]
I will add word-wrap CSS tags to all the templates for the next release, but this only works in Draft-CSS3 capable browsers (Opera 9.6, Firefox 3.5, Safari 3, but not IE8). I am currently working on another, standalone Joomla extension (that will only extend JoomlaComment for now) with an advanced, intelligent Browser Agent checker that makes the adjustments in realtime via JavaScript, but there's no release date for it as it's only in prototype stages (i'm still learning Joomla development).
I just took a look at the Chunk URL Wordpress plugin, it would be very easy to make this auto-link-and-shorten feature for the next release of JoomlaComment I think - I could do it in 5 minutes with JavaScript, but my PHP skill is novice at best.