It might just be that social network interfaces interact with users more intimately, and thus are more problematic to toy around with.
Either way, Facebook's chameleon interface is definitely irritating. You can see some of their design anti-patterns here: http://wiki.darkpatterns.org/wiki/Home
Facebook unveils roughly 8 anti-patterns with every re-do and rolls back the most egregious 4. The result is Facebook get significantly worse with every iteration.
Most of the recent ones though, I've solved with NoScript and only browsing Facebook in a dedicated browser. (I really need to make something a little more robust; effectively a Facebook app running on a Webkit core that opens all external links in Firefox. That would sandbox the social graph, and let me read links out of Facebook normally.)
This sounds really nice, but doesn't facebook also do the sa=D-style redirects like google? (I've no way to check.) If so, it effectively becomes a nice cross-browser way of tracking you.
(For example: http://www.google.com/url?sa=D&q=http://haskell.org/hask... )