yes, this does, in theory work. An AP7 file should load just fine.
However, if you're using lots of beatmapped audio clips you may see issues in your imported project. For me, if I go back and load an old AP7 project with lots of long beatmapped clips I see the beatmap information is not working or corrupt (e.g. I have multiple downbeats or just crazy beatmap markers).
This is because the beatmapper has been updated since AP7, and it stores the beatmap information inside a clip's .SFK file differently. The work around is to re-run the beatmap wizard on these clips.
If you have not purchased AP10 yet I suggest trial the application to see if it works as you need it to.
That's actually one of the few things that I am not having too many problems with right now. I can easily open Acid 7 files, and as long as Acid 10 has currently recogized my VSTs everything works fine...
...however it doesn't always recognize my VSTs and sometimes one will show up for a session, and sometimes it won't(I'm starting to narrow down which ones are problematic). There seems to be a problem with older VSTs, but loading the files works fine so far.