Judging from the comments below that form, that post is from April 2010... So I wouldn't be surprised if the page you go to after signing up actually has disappeared. But still, it looks like it's just asking for beta testers for their Kobo app and Kobo readers. You can still offer to become a beta tester by PMing one of the Kobo reps here on mobile reads. For instance, try
mdclements or
MDK.