Google search does not use the same technique.
* User browses on Twitter, clicks link in tweet pointing to t.co, is redirected off to the page where they wanted to go.
* User searches on Google, clicks link in search result pointing to google.com, is redirected off to the page where they wanted to go.
Admittedly it only happens with half of the search results of the first page (I think; it seems to vary), but it's very much the same technique.
1. That Twitter uses a "short link" where Google uses some kind of (I trust) token-secured "open redirect"
or
2. That Google uses a {Javascript, 301, ...} redirect where Twitter uses a {Javascript, 301, ...} redirect.
Depending on what User-agent I sent, I got Twitter to variously return a Javascript or 301 Moved Permanently response. I could only get Google to return a Javascript response to cURL, but I did not try hard, and I would not rule out Google employing different redirect methods, particularly on their search results page. Google is notorious for falling back to different methods depending on the particulars of the client. See:
http://www.stevesouders.com/blog/2010/07/12/velocity-forcing...
So they at least both use the Javascript method. In any event, if you mod out the content of the hyperlink after the domain, and mod out the content of the text based HTTP response (!), which is fair here, then the methods are all equivalent, and all generate the same server diagrams.
In this case, there is not much difference between the browser parsing plaintext in HTTP headers that tells it to go to a different site and the browser parsing plaintext in an HTTP body that tells it to go to a different site once executed in a Javascript engine.
Can't they do something where the HREF is left intact, but an additional onClick is added to track clicks?