The first 10 images you upload to a public profile will count towards your score - that's to stop indiscriminate uploads of less useful things, like a whole album of baby photos added to a private profile.
Apparently tracking will be done automatically, but there hasn't been any more info on how that happens. Also I'm not sure if it's going to be 10 total that the profile is linked to, including what's there already, or 10 added during the 'thon.