I think it has to be pretty official since in order to be a voting member of the Jedi Council you have to be recognized by the Order as a Master. And yes, there are three official levels of Jedi, Padawans, Knights, and Masters. To go from Padawan to Knight you must successfully complete the Jedi Trials to be recognized as such. This was waved for Obi Wan because he killed Darth Time Filler (stealing ConfusedMatthew's name for Maul). Once you have become a Knight you can be given a Padawan, and if you trained them well enough to pass the Trials themselves, you will be made a Master.