Hi nap,
I think it's possible that we can put the date on the hover over name, but you know if you click the name you can see that information from their profile.
As for changing the signup dates, that's a little trickier. I can, of course, set everyone's join date as the day that we officially launch the site. I guess I hadn't thought about it. Right now, everyone has the same date as when they joined cubits because I copied over the entire profile for everyone.