You bet they have. The city centre is currently full of language students visiting Oxford from Europe to study English for a month in the school holidays, and they go around in groups, of about 50. These groups come all over summer to see a bit of England and also study English.
The other group that I have noticed more over the last few weeks are the Americans, who are either studying short courses but on by Oxford University or just your normal tourist. Where ever they come from they are all looking for the Postcards and to exchange their local currency for the good old British Pound. Good on them and Welcome to Oxford.