Resurrecting a sort of old thread here, but FYI, booting off a Lion install thumb drive made from the AppleStore download (10.7.4), I'm zeroing out the internal 64GB SSD of my 2010 MBA right now using the "diskutil" command in terminal.
Instructions:
- After booting off the thumb drive choose "Terminal" from the "Utilities" menu.
- Type "diskutil info" to get a list of your devices and write down the identifier of the SSD you want to erase ("diskX" with X being a number). It was "disk0" for me.
- Type "diskutil zeroDisk <diskX>" with diskX being the indentifier of your SSD.
This will start the zeroing process. I've heard somewhere that this whole process doesn't make sense due to the way data is dealt with when written to an SSD (wear leveling), but I just feel safer this way if I want to sell my MBA or the SSD.