Finally there is a 67 page Ωmega introductory text. Well, actually it is a delta to Haskell, so the audience is Haskell (and perhaps OCaml) savvy folk, but at least one does not need to collect all the information from the scattered papers.
From the first glance I had at it, it describes all the new features neatly, although sometimes the old "#n" notation sneaks in (the new notation is 1v and 1t, for values resp. types).
I guess this is a live document and Tim together with Nathan will keep it current, cleaning up the few anachronisms as they go.
I am using Ωmega more than a year now, and can only say that it is a remarkably powerful system. (I shall come back with a more detailed and subjective analysis some other day.)
The thing that fascinates me most, however, is the astonishing stability of this product. Being essentially a one-man show, Tim corrected dozens of errors, that I mailed him, or filed in the new issue tracker at googlecode. It is really hard to find any more serious bugs in the core system. This is also a consequence of Ωmega being written in Haskell, so it inherits all of Haskell's blessings. I wish I were a good Haskell hacker, then I would fix the bugs myself :-/
The only drawback at the moment is that it is an interpreter, and this fact makes it a bit slow. So a performant version is needed. Then one can think of bootstrapping the interpreter/compiler. Ωmega written in itself would definitely be the dream of formal methods coming true!