The problem has to do with the temperature you write at and the temperature you store it at. If, for some reason, you're writing in a very cold environment and storing in a very hot one the lifespan is diminished. If it's the opposite, you're golden.
The title is pure irony ("SSD Storage - Ignorance of Technology is No Excuse"). See an another link posted here. Also from personal experience I have had no problem with an SSD that wasn't powered for 7 days.
The author of that piece is actually somewhat confused about how SSDs work. Data retention is a matter of the charge store leaking. An SSD doesn't have any means of refreshing that charge on it's own, the same timer is there whether the drive is on or off. And in fact it will lose data faster if the drive is on since then the drive temperature will be higher. Luckily this sort of data loss isn't a big deal in practice for the reasons outlined elsewhere in this thread.