I just thought it was nice that they actually checked our app, and told us to clearly warn our users about background GPS.
They've done this sort of thing a lot to our apps. One game we had still had placeholder art. They found it, rejected it, and told us to fix the placeholder art.
I also like that they reject outright if your app crashes during the review process.
Sadly, I think they have been getting more and more lenient as the sheer volume of App submissions increases.