Basically what I do with the changelogs on MAMEInfo is go through them and look for entries that say "Renamed files for set X", "Renamed sets to match X", "Added new Y roms to set X", or something similar. Another way is to visit a MAME resource database like MAWS. Search for your sets there and look at their change history across MAME versions. Granted, 9 times out of 10 the MAME changes affect MAME emulation routines only, and not so much the contents or names of individual romsets and the files within. Like Robert said, rom managers can identify outdated sets fast and easy. I've never used one myself apart from curiosity, and because I don't think I need one. They are not very difficult to use. Furthermore, MAME itself is also a pretty good indicator if your sets are outdated in the sense that romsets that it can't "find" when you scan for available romsets never appear or appear as corrupt or incomplete. When you try to run one of these sets, MAME will tell you what files it is unable to load.