Currently, no. However the upcoming 2.6 version DOES give a full user panel for users to view / edit / cancel registrations and make additional payments. For Pay Later items, YOU need to mark them as paid in the backend. We will never give the user control to mark themself as Paid.
hhahahaha damnit - I just upgraded to 2.5.9 - should have waited as i'm liking what I'm hearing in this thread about 2.6!
Is it also going to be possible for users to copy previous registrations to new events. I have an event that occurs every year which needs the same info as the last year but may be altered slightly and possibly include an extra or two fields?!
Also is there a close off date for how long a user can edit details (eg 2 days before event, day of event , 1 week before etc etc)