Do SSDs support SMART?

Yes, they have it, and yes, it's useful.

Flash drives do develop errors over time, usually in the form of bad flash blocks - not unlike bad sectors in regular hard drives.

Just like regular hard drives, the drive controller keeps track of these bad blocks and re-maps them to 'extra' blocks that were saved for this purpose. Whenever the computer requests data from a bad block, the controller intercepts it and gives it the correct data from the re-mapped block.

Eventually you'll run out of extra blocks and will start getting real errors, at which time you'll need to replace the drive - SMART will keep you on top of this so you can take care of it before you start losing data.

The one major advantage SSDs have over regular drives in this is that the extra blocks in a regular drive require head seeks to another track, so as the drive ages it gets slower. In an SSD the remapping is done almost transparently, and so no additional time is wasted seeking to the remapped block and then seeking back to read the rest of the data.

Not all SSDs have SMART support, so it pays to check before you buy if you're concerned.

The Intel models definitely do, and the Supertalent models don't (or at least, the ones i've seen - duradrive and ultradrive).

Somewhat amusingly, the Intel X25-E drive still reports the "spin up time" and "start/stop count" SMART attributes, even though these are never updated and have no practical relevance for non-spinning media.