Not any different from an HDD format.
If you want to make the drive completely blank again, you need to do a Secure Erase.. which is different from a format and significantly trickier.
I don't think there is much point however, if you set up Windows 7, when you format the drive, it issues a TRIM command to wipe the entire drive... whether or not the drive does anything with that TRIM is up to the drive, but Windows has done it's bit.
I wouldn't worry about it, and just when you're installing, delete the old partition(s), and then choose to install to the unallocated space, which Win 7 Setup will then partition and format for you.