It's entirely dependent on the DM and how he approaches the world. In particular, it's value depends on the assumption that the DM is using 'small world' railroading techniques, otherwise the ability is not only useless but is more likely to provide misleading information than actually useful information.
For example, there is for example literally no where in my campaign world that there aren't fey within 1 mile of anyone's location. In fact, the density of fey is probably several dozen per square mile. Sprites are scarcely less common than rats, and household faeries, quiescent dryads and hamadryads, and meadow spirits are all over the place. Rarely does a pond not have at least 1 nixie in it, and every single brook, stream, or spring that doesn't completely dry up every year has a nymph or similar creature. And it would be equally rare for their to be no undead within 1 mile of location that had ever been habited. Whether it is a haunt, apparition, phantasm or low level ghost that only shows up on nights of the full moon that coincide with the anniversary of some tragic event to reinact a past tragedy, or a hunting vampire would be useful information - but that isn't provided. Dragons would provoke all sorts of false positives, as you'd be picking up mini-drakes, wood drakes, spire drakes, and dozens of other species that are scarcely more important to know about than owls, minks, alligators or bears. Knowing the hit dice of the largest creature you are detecting might serve well as an early warning system, but that isn't part of the spell. Picking up celestials and fiends would be somewhat more unusual, but not entirely unusual, and the answer to, "Are their evil spirits in this city?", is almost certainly, "Yes." Whether it's a demonic cult or simply a pact bound fiend guarding the ancient altar to some blood thirsty god of commerce or revenge in the glade of yews in the temple district that people go into only after midnight isn't a question the spell answers. However, the very fact that the city doesn't disturb the alter for fear of offending Hades or his equivalent, and hasn't done so any time in the last 2000 years, ought to tell you that the town father's probably aren't going to be happy with you for rousing a deities wrath. The elementals question can be asked more simply, "Are their any rocks larger than a bread basket within a mile?", if so there are certainly elementals quietly slumbering and dreaming dreams of solidity and stone. Aberrations are really rare, so the presence of one is a pretty big warning flag, but warning about what? Aberration is a catch all category for "weird stuff not related to anything else". What are you going to prepare for?
In short, assuming that the world is presumed to be "lived in", the power is useless. It's only useful if the only salient features of the game world are precisely the ones the player's would be interested in because those are the only features of the world that exist.
This is a problem I usually have to train my player's out of. Just because there is a temple to the god of traps on the out skirts of the village doesn't mean that the priesthood has anything to do with the latest murder, and barging in (often on the suggestion of the real murderer) unannounced and breaking stuff just means you are entering a trap and making enemies you wouldn't have had otherwise. It's just there because in the real world, there are all sorts of complexities that result from people living somewhere and I was trying to flesh out the local culture.