There's a tool that already does this

I think this tool does it for WordPress.
I spend most of today creating a plugin for Nucleus (which is what I use). It is active now and works in combination with the WakkaWiki tool I (and you yourself) use as the base for the ICT in het Onderwijs Wiki (it works with WackoWiki also). You can now use either WikiWords or the WakkaWiki syntax for forced links (using [[wikiword description]] syntax. It works in both the posts and in the comments.
For the posts it also 'tracks' references to Wiki pages. That means that if in a post I link to a WikiWord, then on the Wiki-page for that WikiWord you can see that a post on my blog links to that page. The plugin hasn't been published yet, will do that once I've tweaked it a bit more.

In general I think both wiki and weblog have their own purpose. Though the wiki has been very open and we've invited people to contribute, it is an even bigger step than replying to a post in the weblog. But for broader topics, less time-related things the wiki is nice to post.

p.s. both wiki and weblog are in Dutch, but even if you can't read Dutch, you should be able to understand how it works from this example post (look for the questionmark links and the link to "WakkaWiki", those are created automatically).

When I was writing the commenting system for my blog, I originally thought to use a wiki. It was easy enough to create. But in the end I decided against it, because many people don't know about editing wikis, and I didn't want a commenting system that required people to learn something new.

Maybe not as a replacement but as a complement. If I want to comment, I want to sign it with my name. If everyone does that on a wikipage you have ExtremeThreadMode which will probably just create a mess than be useful. What is more is that it is more difficult to follow what people reply to your comments on a wiki than on a blog.

Also, many comments are not useful anymore after a while (questions that have been asked have been answered, the discussion moves on...). Do you want to archive that on a wikipage? Who is going to do the editing? Are you going to delete readers' comments? Are they? (In a weblog they are fine - they move to the archives and are no longer in the way. If you pick up the topic another time you link and the discussion can start again in the new entry's comments.)

I can see many ways in which blog and wiki can complement eachother but I wouldn't convert blog-comments to edits of wikipages. It's just something different, editing a wikipage and commenting a blogpost. It's a different form of conversation taking place. How would we have had this discussion on a wiki?

(Just looked through my archives: I have some links on the topic to pieces by Clay Shirky and Ross Mayfield over in this old post.)

Hi all,
thanks for responding! I can see the differences between commenting and wiki as media for interaction, and the suggestion to see them as complements is a useful one.

That a wiki indeed might be confusing for commenters, as Dale suggested, is something that can be overcome I think. This because the confusement is probably in the way Wikis usually are laid out. In my wiki I've already started to recreate the look and feel of my blog. This makes it a more singular space, even if the scripts behind them are different.

Enhancing the wiki lay out to make it resemble the blog even more, and making the difference in environment next to invisible except for one thing: the edit-button, will be a next step forward.

So I will be looking into the tool for WP Pierre suggested, and am also curious as to his own plug in he wrote for Nucleus. And I think I'll play around with this a bit more before settling on a solution.

Nice, Santa is coming to town. This was exactly one of the items I put on my personal wish-list for blogging tools sometime in April (http://notizen.typepad.com/aus_der_provinz/2004/04/wunschliste_fr_.html; sorry, in German only) which was inspired by Dave Winers call for suggestions "A vision for the next generation of blogging tools?" (http://blogs.law.harvard.edu/bloggerCon/2004/02/24)

Like Martin and Pierre, I don't think that it is the best idea to generally replace the simple commenting of most current blogging tools with a wiki. If all I want to do is sent a short comment, current commenting functionality is up the task. If I would like to initiate a process, which leads to a common "result" produced by a group of people (collaboration? on some kind of document), wikis are much better. Martin's link and the discussions behind his docment contain a lot of IMHO very valuable points for the different strengths and weaknesses of Wikis and Blogs/Comments.

With regard to the "ease of use" of wikis: That definitely can be overcome. I know, that it is not fashionable among the current blogging crowd to suggest this. But I still don't see where the big problem is with a WYSIWYG editor for blog entries and even wikis. Blogger.com shows, that his is possible with current technology on the server- and browser-side. Admitted, the wiki notation is not that hard to learn. But why should the user have to learn anything at all (which is not related in any way to the real "purpose" of what I am trying to accomplish with some tool)

Personal Webpublishing (not only blogging) and the tools used to do it are still in their infancy. Only some of the usage patterns, which im some years will be deemed "most important" have emerged already and even less are supported by the functionalities of current tools. A first step towards a richer set of tools would actually be the merging of the different "schools" of publishing software. Another should be the reduction of purely administrative overhead But I don't think, it will stop there.

http://viabloga.com/ and http://joueb.com/ add wiki functionality to weblogs.

http://upian.net/znarf/carnet/ uses a "wiki field" instead of comments.

The new app I just sent you to beta-test will do this (very) shortly. Any item of microcontent, or items stitched together and finished off in the Editor, can then be posted to a range of destinations (depending upon the API's). We will be continuously adding more publishing destinations, as we move towards a Post-To-Anywhere capability ... so the tool will be able to function as a "bridge" between blogs and Wikis (I think - pretty sure at this stage).

Marrying wikis with blogs is definitely a good idea. Meanwhile (untill they're all married ;) this question:
When I've written a wiki-page related to someone else's blog-entry - Is there a way to "manually" send the blog a trackback that points to the wiki-page?