Yes, people with German ancestry will probably have similar results. In FTDNA's BGA analysis, the only reference population they use for all of northwest Europe is from the Orkney Islands. So most people with Irish, British, German, Scandinavian, and some French and central European ancestry test as Orcadian. Most people with significant Italian ancestry will exhibit some percentage Middle Eastern in any BGA test.
Ancestry hasn't disclosed what reference populations they're using, to my knowledge. It wouldn't surprise me if their "British Isles" is the ubiquitous CEU population in the HapMap project (http://www.broadinstitute.org/~debakker/p3.html
), which are a group of 180 "Utah residents with Northern and Western European ancestry."
One thing people need to realize, and Ancestry hasn't explained, is that even a large percentage from some area doesn't necessarily mean you have any ancestry from there. All it means is that your autosomal DNA is similar to the reference population Ancestry is using to represent that area.