@la_serpe: I have read claims that with the leveling technologies we have today and under "normal" desktop use, the rest of any machine would wear out before the SSD would lose significant capacity. Even if it would: In two years, they will be larger and cheaper by multitudes and most of the complainers today would exchange them anyway.
From what I understand, this may be a good option down the road, but the FS needs a bit more work before Ubuntu uses it as the SSD default. (Just my opinion)