I’m toying with the idea to write a powerful wiki engine for Eclipse. What I have in mind should
- Allow multiple markups (because all markups suck, so there is no point to prefer one over the other)
- Should offer a side-by-side editor (source and preview because WYSIWYG is impossible to get right)
- Should support automatic links (just like in the Java editor)
Right now, I’m not sure whether I should start with Mylin WikiText or Xtext.
Both look promising. WikiText support multiple markups. I just don’t like the two-page editor (where you have to flip pages to see what you’re doing). Also, I’m not sure how flexible the whole framework is.
Xtext would allow for much more complex markups but I’ll probably have to start with a more basic framework.
Links: Extending RIM with Xtext
Dark Views 
We considered writing a Wiki-like documentation platform using Xtext when we needed something decent to document Xtext itself.
We eventually decided not to invent yet another wiki, but instead use WikiText. Main reasons were:
(a) WikiText is readily available and had 95% of the features we needed.
(b) WikiText is very flexible with respect to both input (you can choose among a number of well-known Wiki dialectsor even write your own) and output (HTML, Eclipse Help, DocBook).
(c) More people know WikiText and the Wiki dialects that it supports than any homegrown Wiki dialect we’d have come up with.
We filled the 5% gap by implementing some additional keywords that basically allow us to link into CVS. So far, we didn’t regret choosing WikiText.
However, you should be able to write a Wiki engine with Xtext. Go ahead and let us know how you make progress!
Thanks for the info. I’ll post a follow up after giving both a whirl.