Hi. we have moodle 2.2 and a 3rd party user import script, which imports everything: users, courses, enrolments, grades to moodle from our database. We plan to upgrade moodle to at least 2.5v. Are there any API changes in these versions that might fail our synchronization? especialy in user import.
If you are asking about web service changes in Moodle 2.5 and onward I would suggest to take a look at these two documents