I also believe that some screen readers would assume the links were prose and read as one sentence without pausing making it very awkward.
In SayAll or similar it'll sound like one sentence anyway:
link home link contact link products link press relations link privacy
But since they are focusable elements you can choose to listen to one at a time with tab or some shortcut whether it's in a proper list or just a div full of anchors.
The difference in readers when you have a proper list appears when you "go down a line". Orca can just skip the whole ul as if it were a single line if you want, which can be nice. in JAWS each "new line" would be the next link, so to skip out of that you can "n" (next non-link text).
When the links are just loose anchors in a box, they'll not have the go-down-one-line behaviour; they'll be like a bunch of links within a paragraph. Since "link" is announced before each one, you know either way it's a bunch of links (this gets annoying in Wikipedia!!).
What you miss with a bunch of anchors in a box is, the ability to skip TO that list (edit, a modern reader can let you skip to the navigation landmark aria role, and nav is supposed to have that role by default, but few browsers and AT actually see/add that role to nav yet). A bunch of anchors isn't anything; a list is a structure you can choose to visit, count, backwards and forwards. Using <nav> with loose anchors inside might tell the AT that these links are part of "main site navigation" (of course, this is up to the developer and may vary widely, so may not mean anything to the visitor anyway) but you can't jump to that list using a quick key because instead of a list, it's a jumble of links.
I actually haven't seen a site lately who wrapped an anchor around a block to test, but what the reader does is likely based on what the browser does. Remember when I had that typo <a/> and Firefox created all these new "anchors" from the text that followed? Orca announced those as anchors, JAWS did not... IE did not show the following text as anchors and JAWS equally ignored them.
I wouldn't count on AT being able to click on an anchor wrapping a block with HTML5 until after testing, because it seems AT vendors would have AT ignore that with HTML4 since it was usually a mistake.
Something I should go look at.