I don't have the expertise in that area, but one comment I'd like to make is that when we're talking about personal information, what are we talking about? Certainly, I've seen the Australian form, and I presume ours would be somewhat similar. Basically all you're asking for is all of the information that's on your passport: your name, your address, your date of birth, your citizenship, the purpose of your visit, and whether you've ever had a criminal offence. There's not much more than that on the Australian one. Surely that's not information that you can't share with others, because everybody knows it or can get it by looking in the phone book, basically.
On November 19th, 2012. See this statement in context.