I just searched my email to find my notification of signing that petition (thank you for reminding me to do that novastar) - and my number on the list corresponds with the number on the petition. So I think that's pretty cut and dried.
I didn't sign using my full name though - I never share my full surname on sites like that - so that's something at least.
At least I don't use the same passwords wherever I go - I use so many different ones that I keep a (paper) list - and I've also made sure that my TSR password does not correspond to any others on that list.