Q:

Chromium browser bundle

What is the current state of porting the TBB from Firefox to Chromium?  Several years back the Tor Project blog mentioned work by the Chromium developers to implement the needed APIs; since then, nothing.  Chromium seems to be far more advanced than Firefox in many respects: it has process separation, full sandboxing, and generally robust security.  The Chromium Project is open-source, and therefore arguably safe from government interference and backdoors, and user tracking should be a simple matter to remove. The blog post claimed that a good deal of work had been done to this effect, and that if the APIs were completed, the functionality would in fact be much simpler to implement than in Firefox. Also, with Opera now based on Chromium, it would seem that working on a Chromium bundle would make porting to Opera, SRWare Iron, and many others simple.

Has this work stalled?
If so, why?
Is there any chance it will continue?

Links:

https://blog.torproject.org/blog/google-chrome-incognito-mode-tor-and-fingerprinting
https://blog.torproject.org/blog/improving-private-browsing-modes-do-not-track-vs-real-privacy-design

UPDATE:
I've reviewed the link mrphs provided and done some research.  It seems that of the five blocking issues listed, most are obsolete, fixed, or on the way there, and only one major problem remains for which there is no workaround.  It would be nice to see the Chrome bug list reviewed for updates.
UPDATE:
According to the conversation around that last major problem, a custom Chrome build would make it feasible.  It seems that the Tor Project is waiting until they can make an extension-only version of TorButton for Chrome, rather than a fully custom fork like Firefox.  Interesting thought: if something this simple became possible for Chrome, would Firefox be dumped?
In summary, progress is happening, but largely stuck on a few issues.

A:

"... and user tracking should be a simple matter to remove."

That's the tricky part. It's rather impossible than simple.
There are several fingerprinting and privacy related bugs which seem to be impossible to patch.
For more detailed info see: https://trac.torproject.org/projects/tor/wiki/doc/ImportantGoogleChromeBugs

