Life in a 5-d hole
The answer to what it would be like is that it would be remarkably similar to what we see. These 5-d ones aren't like the familar four-dimensional (that's three of space, and one of time) black holes - and by 'familiar' I mean that even if you don't have much of a grasp on general relativity, you'll probably get the idea from if you get too close to one, it'll suck you in, rip you apart, and not even your constituent atoms will be seen again.
These 5-d ones are much friendlier places to hang around. And handily, there's plenty of circumstantial evidence that suggests that the universe has at least five dimensions, otherwise it just shouldn't work in the way that it apparently does. A 5-d universe just wouldn't look any different to what we see as a 4-d one.
The most persuasive clue found by Wesson is that the universe (as it would be in a variant of the big bang model dubbed the 'big bounce', which seems to demand five dimensions) looks remarkably like a hypothetical five-dimensional black hole, if you look at a ballpark measure of their physical characteristics called the Kretschman Scalar. This measure basically measures the gravitational field at some point in space, and takes a variety of dimensional forms for different models - but in these two cases, it comes out very similar. As Wesson says:
It is conceivable that a bouncing universe and a 5D black hole could have identical Kretschmann scalars by coincidence alone, but given the number of parameters involved, it is very unlikely. Much more likely is that there is some kind of similarity between the two objects.
Intriguing stuff, that demands further investigation. Wesson throws in a coda illustrating the possible ramifications, albeit in a way that risks drawing in the astral-travelling crowd:
We are led to consider the idea of a set of "Russian doll universes", with each world embedded in another world of higher dimensions. There is as yet no way to know what we will discover when we probe these higher-dimensional universes.