Of course they give you the general "where you are from" map. Naturally it can't break apart countries at the lines because our ancestors didn't act like that and so the DNA can't tell you "you're from Switzerland because that in itself is a complicated mix. However Ancestry tries their best and claims to be the most specific of any DNA test out there. (I choose Ancestry because I felt their database would be the biggest). One common complaint against Ancestry's test in this case is that they give no specifics about which sections of your DNA match up with someone who is supposedly close to you... You can imagine how this would be helpful to the intense or casual researcher.
Comparing matches: There are many people who have already taken the test so that's great however not all have attached their results to a tree. I would highly suggest you do this and I'll explain how. This is beneficial because where Ancestry doesn't tell you where you match it does give you ancestral hints which compares your tree and lets you know that you have people who appear to be the same people in both your trees.
However it would take a long time to insert a Ancestry.com tree to match your FamilySearch Tree for most. I intend to show you it's not that difficult to insert your FamilySearch tree onto Ancestry.
First download a program which can extract your tree I would suggest Ancestral Quest Basics because it worked for me.
Second within Ancestral Quest -- Log into your FamilySearch account (FamilySearch --> Log in) and download at least 15 generations (do more if you want but it takes a lot of time) for BOTH lines. This will take SOME TIME seriously it took quite a while so go and make dinner and eat it while it's happening.
Third save this as a GEDCOM file (File --> Export --> Other I think or it doesn't matter) once it is exported open your account of Ancestry.com and under the trees there is a Upload GEDCOM option. If you do this it will upload your gedcom as a new Tree
Fourth go to your DNA test results and attach yourself using the new tree.
I guarantee you'll see some ancestral hints (it took a day to register for me).
This is a very interesting section of Family History which I can't wait to see unfold. I also hope that Ancestry makes it possible to see the base information for my own DNA that would be interesting and also then where my DNA compares with someone else exactly where we compare.
I also guarantee you'll find some sections of your tree have no hints with others. Barring the obvious "no one from that line took the test" or "they just haven't filled out their tree that far" It would then suggest that the physical DNA doesn't match up to your Record line. Ergo a child was adopted in there or the person listed isn't really the father. Again I haven't had success pinning anything NEW down with this test but I just find it interesting