Don't quote me on this... but from what I've read, Panda 2/2.5 is also going to effect spun content. Not sure on how well it is going to work right off the bat in detecting like-sayings, and like-words, however I'm sure like everything else, Google will stubbornly work hard at it and master it. I wouldn't underestimate Google, they have some rather brilliant engineers and developers over there.
It wouldn't be that difficult for them detect like sayings or spun content, especially with the amount of data Googlebot crawls over, and words that it sees. I'm sure it can easily pick up on a percentage of how unique one page is to another, and from there they'll be able to detect duplicated content, even when spun.
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Though, spinning content is cheap and easy... there are plenty of other ways that tend to be more time consuming or a tad more costly that guarantee you won't be effected by Panda.