I just found that great piece of software and love that clean and easy design.
But I found two things that would be nice to have:
It would be a great thing if there could be a new user role (I'd call it "public").
The Permission for that user must be
+ create a ticket
+ view ticket(s) created by that user
+ add comments
+ recieve alerts (change of status, new comment, ticket closed/resolved)
In most cases an enduser will find a bug and want's to report it - that is at the moment not possible.
Also it would be nice if there would be a read only access level.
e.g. for project leaders - that they can have a look at open tickets but can't change anything.