Userpics Support volunteers occasionally field questions from users who think they should have gained 100 additional userpics when they bought the add-on space, rather than the actual 100 total (70 additional). Maybe the distinction needs to be emphasised a little more in the FAQ. I propose rewording this bit:
"Paid users can purchase add-on userpic space for 100 total userpics."
to something more like
"Paid users can purchase add-on userpic space. This will give you an additional 70 userpics, for a total of 100 userpics."
There's bound to be reasons why this is not a good idea. Let's hear 'em :)
ETA: Also, the max userpics for Permanent accounts is now 199.