Tor browser probably never will include an ad blocker, like we do. See: 2.3.5: No filters
As long as we keep an ad blocker that prevents downloading the ads our browser fingerprint will be quite different from the Tor browser's.
Sure, the browser fingerprinting issue is a real one; I wonder if this is going to be more and more true anyway, with torbrowser diverging more and more from iceweasel + torbutton.
We could of course remedy this by using an ad blocker which downloads the ads but just hides the elements, but this sort of defeats what I suppose is the main reason for us to have an ad blocker: to reduce the lag introduced by downloading ads that usually are larger than the target sites themselves.
Making it harder for advertising networks to track Tails users is another reason I see to keep AdBlock. The torbrowser design document reads "these addons do not add any real privacy to a proper implementation of the above privacy requirements, as all third parties are prevented from tracking users between sites by the implementation"; we should read the Implementation section in details, see if this is true for iceweasel + torbutton, or merely for torbrowser. Thus tagging research too.
(Long, hard to follow discussion moved to the discussion page.)
So, what are you going to do about Adblock? Are you talking with Tor developers about this?
Current status: stalled. We are going to discuss Tails relationship with the Torbrowser, especially on the browser fingerprinting, anonymity set and ad blocking topics, during the northern hemisphere's summer 2012.
Current status: waiting for the notes of the aforementioned discussion to be converted into ticket updates [anonym]. Thus removing the obsolete tags.