I agree with Tony Keene on this. The IOC have a great set of rules but end up with a lousy set of names – particularly for Australian birds. Bird Life International maintain a very good world list with “under review” and “not recognised” for questionable names. I use a world list built from the HBW based on the fact that it is more than just a list (a picture, map, text, list of subspecies, references and comments on how others treat a particular species etc). Where later splits are recommended by the like of BLI or IOC or C&B I can usually find the appropriate subspecies within the HBW, and typically these subspecies have been illustrated. But the big advantage of HBW is that most of the family accounts on species of Australasian distribution have been written by Australians and the names most closely follow what is used in the field guides here. I assign a number based on a 3 digit family designation added to the 3 digit species number in the text with a 2 digit decimal number for subspecies and this allows me to keep track of different birds I’ve seen in different countries and manage a non-overlapping world life list and insert splits when they occur/are agreed upon. My rule for recognising species is that if either BLI or HBW recognises it then its good enough for me. That way I also get 3 Shrike-tits to tick as an added bonus!