[eeyore]

just to point out that i have beeen taking photographs in publuc as well as privately for years and have never had a problem - it comes down to commonsense really , if you are going to take portraits of kids talk to the parents first , and if they ask you not to , dont

if the police approach you be courteous , explain what you are doing and show them the pics (assuming that you are a digital user of course) - there was an article on this gray area in last months proffesional photographer magazine which is well worth a look